Mineral Essay

Comments on Initial Essays
EMSC 121

Essay

I've never really thought extensively about how mineralsaffect my life until I started taking this course.  Minerals are everywhereand it never occurred to me that my life would be so different withoutthem.  As I start my day, I take for granted that I have a place tolive.  Without minerals, I would be homeless.  Minerals are thekey components in the foundation of my apartment building.  They arewhat make my building strong and secure.  When I walk in my bathroom,I take for granted that I have tiles on my floor and in the bath tub. And when I look in the mirror to put on my gold and silver jewelry (althoughI never wear both together because that is a big fashion No-No), I takefor granted that I am able to see myself in my mirror (because of minerals)and to admire my minerals (aka my gold necklace and silver watch). Without minerals, I wouldn't be able to make such a great fashion statement. As I leave my apartment, I take for granted that I have sidewalks and streetsto walk on.  Without minerals, I would be forced to walk through muddyfields and grassy pastures.  Sitting in my computer class, I takefor granted that I have a computer, which uses gold trimmings to operate. After class, I take for granted that I have a car to drive to the grocerystore so that I can buy food.  The list goes on and on.  Mineralsmake all my daily routines a reality.  Without them, life would beso much different.  Yet, it wasn't until I registered to take thisclass that I realized the true importance of minerals in my everyday life.
 Even though I see the great impact of mineralsin my life, I also am concerned with the negative impact of them as well. I have heard horror stories of pollution caused by the extraction of minerals. In this class, I hope to learn the basic concepts regarding minerals butI also hope to learn about the environmental concerns associated with theextraction of minerals.  I want to hear about real issues and concernsthat face society today.  I want to be able to walk away from thisclass with not only a better understanding of minerals but with a trueapplication of the impact of minerals in my life.  I want to gaina better understanding of how minerals are extracted and converted to everydayobjects but I also want to learn why some should not be extracted due toenvironmental concerns.  Overall, I want to be able to walk away fromthis course with knowledge that I can use in my everyday life.
 
 

Comments

I enjoyed reading your essay.  It is thoughtful andinsightful. I offer three sets of comments to consider, as marked by thethree different brackets:
 << scientific content>>, [[tone, structure,organization]], and {{grammar}}. I may have also  removed  (somewords -'dead wood' or 'distracting') and added SOME WORDS, as designatedby parentheses (), or ALL CAPS .

{{need a title for your essay}}
 

 I've never really thought extensively about howminerals affect my life until I started taking this course.  Mineralsare everywhere and it never occurred to me that my life would be so differentwithout them.  [[perhaps another sentence here in introduction andstart a new paragraph for the body of the essay]] As I start my day, Itake for granted that I have a place to live.  Without minerals, Iwould be homeless.  Minerals (are the key components in) CONSTITUTEthe foundation of my apartment building [[Use active voice, and robustverbs.]]  (They are what make my building strong and secure.) (When I walk in my bathroom,) I take for granted that I have tiles on thefloor IN THE BATHROOM. (and in the bath tub.)  And when I look inthe mirror to put on my gold and silver jewelry (although I never wearboth together because that is a big fashion No-No), I take for grantedthat I am able to see myself in my mirror (because of minerals) and toadmire my minerals (aka my gold necklace and silver watch).  Withoutminerals, I wouldn't be able to make such a great fashion statement. [[paragraphbreak]] As I leave my apartment, I take for granted that I have sidewalksand streets to walk on.  Without minerals, I would be forced to walkthrough muddy fields and grassy pastures.  Sitting in my computerclass, I take for granted that I have a computer (,) which uses gold (trimmings)CONDUCTORS to operate.  After class, I take for granted that I havea car to drive to the grocery store so that I can buy food.  The listgoes on and on.  Minerals make LIFE POSSIBLE. (all my daily routinesa reality.)  (Without them, life would be so much different. Yet, it wasn't until I registered to take this class that I realized thetrue importance of minerals in my everyday life.)
 Even though I see the great impact of mineralsin my life, I also am concerned with the negative impact of them as well. I have heard horror stories of pollution caused by the extraction of minerals. In this class, I hope to learn the basic concepts regarding minerals butI also hope to learn about the environmental concerns associated with theextraction of minerals.  I want to hear about real issues and concernsthat face society today.  [[paragraph break to start the conclusion]]I want to be able to walk away from this class with not only a better understandingof minerals but with a true application of the impact of minerals in mylife <<not  clear after "but with..">> .  I want to gaina better understanding of how minerals are extracted and converted to everydayobjects but I also want to learn why some should not be extracted due toenvironmental concerns.  Overall, I want to be able to walk away fromthis course with knowledge that I can use in my everyday life.

<<good examples of minerals along a story line ofa daily routine; good contrast of material benefits versus environmentalcosts>>
[[need to have a well-crafted structure with  separateparagraphs for introduction, body, and conclusion]]
{{Use shorter and simpler sentences with active voice.  Use 'I' less frequently when you can.  It would be difficult to dothat in this essay since you adopted an informal tone. }}
 

Essay
 

           When I was a freshman in high school, I took an Earth Science class thatdealt with many subjects—my favorite being minerals and rocks. I likedthe colors, textures, and shapes of them, and even learning what they areused for in the world. I learned about the different uses for each mineral,what their differences and similarities were, and how to identify them.I only wish I could remember everything I learned! But now that I can’tremember much at all, I’m very excited about taking this class. I knowminerals affect everything around me, and in this class, I can’t wait tolearn about the specific ways they do.

           Minerals are everywhere—from the cars we drive, to the food we eat, tothe jewelry we wear, and even inside our computers. Lead, Aluminum, Silver,Gold, and Sulfur—all of these minerals and many more are used in certainand specific ways every day. I know that without minerals, I would notbe here, as my own body is composed of many of them. I’m very intriguedby the fact that if even one mineral was wiped out of existence—say aluminumwas completely gone forever—our way of life would be drastically changed.We’d have to find another way to build our airplanes, our cars, and a newsubstance to wrap our leftovers in. Or if lead were to disappear, we wouldhave find a new way to build and run electronic applications, televisiontubes, weights, ceramics or crystal glass, foil or wire, and even X-Rayand gamma radiation shielding.

           I hope to learn about how each mineral is specifically used in my life—andaround me. I want to be able to identify minerals in my life—and figureout how each was used to create the things around me—like the walls ofmy dorm room, my desk lamp, and my fish bowl—everything. I really thinkI’m going to enjoy this class. I’m definitely ready to learn.
 

Comments

I enjoyed your essay. It is well structured, and wellwritten.  You obviously did some reading before writing this essay. It includes many examples of mineral uses and a good level of technicalinformation. I offer three sets of comments to consider for your futureessays, as marked by three different brackets:
 << scientific content>>, [[tone, structure,organization]], and {{grammar}}. I may have also  removed  (somewords -either 'dead wood' or 'distracting') and added SOME WORDS, as designatedby parentheses () and ALL CAPS, respectively .
 
 

 {{need a title}}

           When I was a freshman in high school, I took an Earth Science class thatdealt with many subjects, INCLUDING (—my favorite being) minerals and rocks-MY FAVORITE. I liked the colors, textures, and shapes of THE MINERALSAND ROCKS (them, and even learning what they are used for in the world).I learned about the different uses for each mineral, what their differencesand similarities were, and how to identify them. (I only wish I could remembereverything I learned! But now that I can’t remember much at all, I’m veryexcited about taking this class.) I know minerals affect everything aroundme, and in this class, I can’t wait to learn HOW (about the specific waysthey do.) [[did shorten your introduction-it was a little too long fora one-page essay]]

           Minerals are everywhere—from (the) cars (we drive), to (the) food (we eat),to (the) jewelry (we wear), and (even inside our) TO computers. Lead, Aluminum,Silver, Gold, and Sulfur {{no need to capitalize the names of minerals,or metals}}—all (of) these minerals and METALS and many more FIND NUMEROUSDIFFERENT USES (are used in certain and specific ways every day). [[useactive verbs, e.g., 'find' instead of 'are']] I know that without minerals,I would not EXIST (be here), as my own body CONSISTS OF (is composed ofmany of them) MINERALS. (I’m very intrigued by the fact that if even onemineral was wiped out of existence) IT IS INTRIGUING TO THINK THAT REMOVING a SINGLE ELEMENT FROM EXISTENCE—say aluminum-   (was completelygone forever—our way of life) would (be) CHANGE LIFE drastically (changed). We’d have to find another way to build (our) airplanes, (our) cars, anda new substance to wrap (our) leftovers in. Or if lead were to disappear,we would have (find) a new way to build and run electronic applications,television tubes, weights, ceramics or crystal glass, foil or wire, andeven X-Ray and gamma radiation shielding.

           I hope to learn about how each mineral is specifically used in my life—andaround me. I want to be able to identify minerals in my life—and figureout how each was used to create the things around me—like the walls ofmy dorm room, my desk lamp, and my fish bowl—everything. I really thinkI’m going to enjoy this class. I’m definitely ready to learn.

[[strong, uplifting conclusion]]

Essay
 

 Minerals are a vital part of how I live my dailylife and how I interact with my surrounding environment.  Withoutminerals we wouldn't have the objects that we use everyday for school,work, and leisure; such as computers, the chairs that we sit on, the buildingsthat we live in, lights, glass, and many other objects that we use everyday and take for granted.  Minerals are used and processed every dayto give us valuable items such as iron, aluminum, the filaments for lightbulbs, gold, silver, and gems for our jewelry, the silicon used in computerchips, and copper used to make wiring, among thousands of other uses. The locating, excavating, mining, processing, refining, distributing, andselling of minerals employ hundreds of thousands of people from our countryand around the world and are major factors in the world’s economy, thesocial interactions among people, and the advancement of the human raceitself.  Minerals are an essential part of life itself, because withoutthem there wouldn’t be much of an Earth left for anything to live on, letalone thrive.

In this class, I'd like to learn about the things thatthe general run of people don't know about minerals and how they are used,and also the types of minerals used for common things that we use all thetime that we don't usually think about.  I took this class becauseI have always been interested in minerals, and since I was a child, havealways liked Earth Science.  I don’t need it to fulfill my GN credits,or even for electives, I took it because I thought it would be interestingand would benefit me in the long run from know about how minerals interactwith us in our everyday life.
 

Comments

I enjoyed reading your essay.  It is concise, andwell-written.  Here are a few general comments in << scientificcontent>>, [[tone, structure, organization]], and {{grammar}} to considerfor future essays.

<<good references to particular uses of differentminerals, different steps involved in the life-cycle of minerals, vitalrole in the economy>>

[[need to structure your essay in three distinct sections:Introduction, body, and conclusion.]]

{{Use simpler sentences, active voice, and strong verbs.See what you think about  your more  "muscular"  and "lean"first sentence: Minerals constitute a vital part of my life and environment.}}
 

Essay

Primary Essay on Minerals

 Once thought about, minerals affect very much ofa normal human being‚s life.  Glancing briefly around my dorm room,I notice so many things that couldn‚t exist without the aid of minerals. The metals used in all of the various electronic equipment, the quartzused in clocks and the glass for mirrors are just a few of the objectsthat need minerals from the earth to be here.
 One main point that I wish to learn from takingthis course is how much and how often society is really affected my minerals. To be quite honest, apart from doing a third grade science project on igneous,sedimentary and metamorphic rocks, my knowledge of minerals is quite limited. The only other educational encounter that I can recall at the moment wasa special I watched on the history channel about copper mining in Butte,Montana.
 Needless to say, I haven‚t been exposed to muchtechnical information on minerals and how they affect society everyday. Though it is not every man‚s dream to learn more about resources that comefrom our earth, I would still like to know a bit more about what goes intorefining these products to make them into what I see every day and howoften I really am affected by them.
 

Comments

 This is a brief and sincere essay.   Hereare a few general comments in << scientific content>>, [[tone, structure,organization]], and {{grammar}} to consider for future essays.

<<Although very low key, you make some referenceto uses of minerals and classification of rocks.  You could add a sentence, or two about copper mining in Butte that has led to oneof the most spectacular Superfund sites. Interest in mineral processing.>>

[[Good organization of the essay with good introduction,somewhat lean body, strong, and funny conclusion.  You could beefup the body a little.  Honest and down-to-earth tone.]]

{{Need simpler, shorter sentences.  See your lastsentence: It takes more than half of your concluding paragraph.}}
 

 Essay

Minerals and Modern Society

To be completely honest, I have never realized the importanceof minerals in our world today.  However, after careful considerationand the brief class introduction, I have come to the conclusion that mineralsplay a significant role in my life. From the tools and objects I use andtake for granted, such as computers, to the jewelry I receive and wearproudly, minerals are everywhere.  In addition, I feel that our societytoday is oblivious to amount of minerals that exist essentially our lives. For example, my mom raised her eyebrows and questioned why I chose to takea course labeled “Minerals and Modern Society”.  She did not see therelevance of studying this topic even though she herself relies on mineralseach and every day.

           Through out this course, I would like to gain a broader view of the useof minerals in our society in the past, present, and future.  Forinstance, I was surprised that gold is a part in computers.  I wouldlike to learn about other objects that are made from minerals and how exactlythey were constructed.  Also, I am not completely sure what a mineralis and is not.  I feel it would be helpful to discuss the major mineralswe use and their specific and common properties.

           Overall, although it is only the first week of the course, I am alreadylearning new and interesting facts concerning minerals.  I hope thatover the next few months I fully understand the properties of mineralsalong with the major role they play in my life and society.  Maybe then I can explain to my mom why she should take this class.
 

Comments
 

I like the personal story line with the "anchor mom" in this essay that nicely ties your introduction and conclusion. It is also well organized, and well written.   Here are a fewgeneral comments in << scientific content>>, [[tone, structure, organization]],and {{grammar}} to consider for future essays.

<<good reference to significant, but usually unrecognized,role of minerals in society, gold in computers,  and a healthy doseof curiosity>>

[[Good organization of ideas, could shorten the introductionand lengthen the body.  Good transitions between sentences and paragraphs.]]

{{Good use of active voice in your sentences.  Thereare a couple of typos and punctuation errors. }}
 

Essay
 

How Minerals Affect My Way of Life

Minerals are important to me because they are everywhere. If I look
around for a moment I notice that everything is composedof some mineral
or another. Minerals are important because they are keysto survival in
the world that I live in. There are minerals used inmaking houses,
buildings, and everyday household items including televisionsets and
even this computer I am using to write this paper. Minerals are made
into the car that I drive and the buildings that I livein.
Minerals are natural resources that are not man madebut come from the
earth‚s surface.  These natural resources find away into every activity
that is done during the day. Natural resources have becomea vital part
in the way that I live. From the time I take a showerin the morning to
the time I go to bed at night I am surrounded by materialscomposed of
minerals.    I never really noticed beforewriting this paper just how
important minerals are to me.  They are very importantto me because my
way of life would not exist without minerals.
Minerals are very important to me because they aid incommunication.
Today, communicating with others is a vital part of society. The
telephone and the computer are composed of minerals andwould not exist
without these natural resources.
   In this class I hope to gain a better understandingof where minerals
come from.  I hope to learn how minerals are madeand what process the
earth goes through to make minerals.

Comments

This is a good personal reflection on minerals. Here are a few general comments in << scientific content>>, [[tone,structure, organization]], and {{grammar}} to consider for future essays.I may have ADDED, or (removed) some words for the sake of completion, accuracy,or better flow.

How Minerals Affect My Way of Life [[good title]]

Minerals are important to me because they are everywhere. If I look
around for a moment I notice that everything is composedof, OR MADE FROM some mineral
or another. Minerals are important because they CONSTITUTE(are) [[active voice]] keys to survival in
the world that I live in. There are minerals used inmaking houses,
buildings, and everyday household items including televisionsets and
even this computer I am using to write this paper. Minerals are made
into (the) cars (that I drive) and (the) buildings (thatI live in).
Minerals are natural resources that are not man madebut come from the
earth‚s surface.  These natural resources find away into every DAILY activity
(that is done during the day). Natural resources havebecome a vital part
in the way that I live <<Natural resources includemore than minerals, such as plants, water, and air.  They have alwaysbeen vital in every way of life.   Need to stick to minerals.>>From the time I take a shower in the morning to
the time I go to bed at night I am surrounded by materials(composed of) MADE FROM
minerals.    I never really noticed beforewriting this paper just how
important minerals are to me.  They are very importantto me because my
way of life would not exist without minerals.
Minerals are very important to me because they aid incommunication.
Today , communicating with others PLAYS (is) a vital(part of) ROLE IN society.  The
telephone and the computer (are composed) CONSIST ofminerals AND METALS  and would not exist
without these natural resources.
   In this class I hope to gain a better understandingof where minerals
come from.  I hope to learn how minerals are made(and what process ) IN the
earth (goes through to make minerals).

[[Generally good organization of ideas, a little repetitive,but good emphasis on why minerals important.   Introduction isa little long, but reads well. ]]

{{Need to use active voice more frequently.}}

<<good references to  various applicationsof minerals, could identify some minerals, or metals by name  >>
 

Essay

My name is .........  I am 20 years old, and
throughout my life, minerals have been a big part of
it.  I live in New Jersey, and minerals are allover
that state. 
Minerals are something we see around us everyday.
Minerals have affected my life because mostly
everything I own, for the most part, came from a
mineral. 
My car is made from steel.  The steel is a metal,
which is a mineral.  Also, the windows in my carcome
from sand.  The sand comes from a mineral. These
minerals give me a form of transportation. 
My house, which is my form of shelter, is also made
from minerals.  The windows in my house keep outthe
cold.  Also the concrete used in making the househas
rocks in it.  These rocks are minerals.  Andthere is
wood used to hold the building up.
 I use a lot of electrical items.  Some ofthese items
include a computer, television, vcr, and many others.
There are many minerals that are used to make the
wires and little computer chips.   Most ofthese
minerals are mostly metals.  Also I play a guitar.
The strings on the guitar are metal, or some a nickel
plating to it.
 I am in this class mostly because itís arequirement.
 But after a few weeks of the class I know I willhave
a little more knowledge about minerals.  I intendto
know what minerals are mostly used in everyday life.
I donít really know a lot about minerals, so
furthering my knowledge on this would be good. It
sounds like an interesting topic.  Also it dealswith
something you see everyday.

Comments
 

I enjoyed reading your essay.  Good personal reflectionon the uses of minerals, well-thought of, well written.  Here area few general comments in << scientific content>>, [[tone, structure,organization]], and {{grammar}} to consider for future essays. I may haveADDED, or (removed) some words for the sake of completion, accuracy, orbetter flow.

[[need a  good title for your essay]]

My name is .......  I am 20 years old, and
(throughout my life,) minerals have been a big part of
MY LIFE (it).  I live in New Jersey, and mineralsare all over
that state <<Is there any state that does not haveminerals?>>.
Minerals (are something we see around) SURROUND [[useactive voice]] us (everyday).
Minerals have affected my life because mostly
everything I own, for the most part, came from a
mineral. 
My car is made from steel.  The steel is a metal,
which is a mineral.  Also, the windows in my carcome
from sand.  The sand comes from a mineral. These
minerals PROVIDE (give me a form of) COMFORTABLE transportation.
My house, (which is) my (form of) shelter, is also made
from minerals.  The windows in my house keep outthe
cold.  Also the concrete used in making the househas
rocks in it.  These rocks CONSIST OF (are) minerals. And there is
wood used to hold the building up.
 I use (a lot of) MANY electrical (items) APPLIANCES. (Some of t)These (items)
include a computer, television, vcr, and many others.
There are many minerals that are used to make the
wires and little computer chips.   Most ofthese
minerals are mostly metals.  Also I play a guitar.
The strings on the guitar are metal, or some a nickel
plating to it.
 I am in this class mostly because itís arequirement.
 But after a few weeks of the class I know I willhave
a little more knowledge about minerals.  I intendto
know what minerals are mostly used in everyday life.
I donít really know a lot about minerals, so
furthering my knowledge on this would be good. It
sounds like an interesting topic.  Also it dealswith
something you see everyday.  [[could shorten yourconclusion for a more crisp ending]]
 

[[good organization of ideas in well constructed paragraphs]]
<<good references to applications of several mineralswith specific information>>
{{use more robust, active sentences}}
 

Essay

Minerals Effect Society
 

           Minerals are all around us.  We use them everyday.  Just lookaround you; it doesn‚t matter what kind of materials you are using. You can be sitting in a plastic chair, or driving in a car, but whateverit may be more than likely it was made from minerals.  This is exactlyhow minerals mainly effect our every day lives.  Of course mineralsdon‚t come from living organisms.  So products such as paper and woodenproducts do not count as minerals.  But as I sit here and go througha serious thought process, I can figure out that I use minerals more thanI would have ever thought. 

           Over the summer months, when I carry on a normal everyday life, I believethat I use minerals more over that span of time than any other time duringthe year.  As I look at the things that I do and the items that Iuse everyday, there are plenty of minerals involved.  The main usageof minerals being my transportation needs.  Transportation servicesinvolve gasoline which is produced from petroleum, a vehicle, and of coursethe roadways and highway systems.  On the side, I also use clays formy dishes to eat off of and I live in a brick house that was produced fromclay.  There are also many electronics and plastics that are usedto help me through life and to survive.  When I pick up the telephoneor turn on the T.V. to enjoy myself, I realize that they are made frommineral based materials too.  Even at this very moment I am involvedwith minerals in my life.  The use of this computer to write my paperis just another example.  It‚s like no matter what I do in today‚ssociety, a majority of the items used are made from minerals.  Aluminum,gold, petroleum, coal, cement, and others are just a few to name. If it weren‚t for the usage of minerals, would it even be possible to carryon an everyday style of living? 

           As far as what I plan on learning in this class, I really don‚t know. The only true expectation that I have for this class is to learn wheresome of these minerals come from and what products are produced from them. I have always been interested in the minerals of the earth, so I figuredthat this would be my chance to learn about them.

           The main theme is that minerals are all around me.  I use them allthe time and don‚t even recognize it.  This is my chance to learnwhere they come from and why we use them so much.  I look forwardto it. 

Comments

This is a good first draft of an essay with free flowingideas.  You need to revise, rewrite, and revise to focus and sharpenit.  Below are a few general comments in << scientific content>>,[[tone, structure, organization]], and {{grammar}} to consider for futureessays.
 

[[Your tone is conversational and a little too informalfor this kind of essay.  Make your sentences self-contained, standon their own.  Structure your essay along a time line, a theme, ora  story. ]]

<<Good reference to some uses of minerals. GIve more specific information. Avoid generalizations.  Yes, plantsand living organisms are not minerals, but some minerals have come fromonce living organisms - e.g., calcium carbonate, CaCO3, as mentioned inclass. >>

{{I strongly recommend that you work with a writing tutor on this essay to start with, and your next essay.  Writing well isan important skill that you can acquire by working hard at it with goodhelp, initially.}}
 
 
 

Minerals (E)Affect {{Affect is the verb.}}Society
 

           Minerals are all around us.  We use them everyday.  Just lookaround you; it doesn‚t matter what kind of materials you are using. You can be sitting in a plastic chair, or driving in a car, but whateverit may be more than likely it was made from minerals.  This is exactlyhow minerals mainly (e)Affect our every day lives.  Of course mineralsdon‚t come from living organisms <<some do!>>.  So productssuch as paper and wooden products do not count as minerals.  But asI sit here and go through a serious thought process, I can figure out thatI use minerals more than I would have ever thought. 

           Over the summer months, when I carry on a normal everyday life, I believethat I use minerals more over that span of time than any other time duringthe year.  As I look at the things that I do and the items that Iuse everyday, there are plenty of minerals involved.  The main usageof minerals being my transportation needs.  Transportation servicesinvolve gasoline which is produced from petroleum, a vehicle, and of coursethe roadways and highway systems.  On the side, I also use clays formy dishes to eat off of and I live in a brick house that was produced fromclay.  There are also many electronics and plastics that are usedto help me through life and to survive.  When I pick up the telephoneor turn on the T.V. to enjoy myself, I realize that they are made frommineral based materials too.  Even at this very moment I am involvedwith minerals in my life.  The use of this computer to write my paperis just another example.  It‚s like no matter what I do in today‚ssociety, a majority of the items used are made from minerals.  Aluminum,gold, petroleum, coal, cement, and others are just a few to name. If it weren‚t for the usage of minerals, would it even be possible to carryon an everyday style of living? 

           As far as what I plan on learning in this class, I really don‚t know. The only true expectation that I have for this class is to learn wheresome of these minerals come from and what products are produced from them. I have always been interested in the minerals of the earth, so I figuredthat this would be my chance to learn about them.

           The main theme is that minerals are all around me.  I use them allthe time and don‚t even recognize it.  This is my chance to learnwhere they come from and why we use them so much.  I look forwardto it.
 

Essay

 Minerals greatly affect the way that people live. From the smallest things
to the largest, minerals have probably played a rolein their formation and
existence.  In this course, I would like to knowmore about the specific
ways in which minerals contribute to our environmentand world.  It would be
interesting to know what exact minerals make up a particularthing (A thing
that we may look at everyday, but not know what it wasmade from).  It was
mentioned in class that the desks and chairs that weuse every day are made
up of minerals.  There are many other items usedin the world that are
important to society that people take for granted. Many think that they are
just what they are: a limestone bathtub, marble floorsand the gems in our
everyday jewelry etc.  However, they fail to realizethat they come from a
much more natural places as well as serve other purposes. During the course
of this class, I would also like to know how mineralsare formed, the
difference between minerals and other natural substancesand the different
kinds of minerals.  It would be interesting to knowwhat classifies
something as mineral and/or the chemical make-up thatit needs to have.
This is important to me because minerals provide a worldfor me to live and
function in.  From the soil that I walk on to theair that I breath,
minerals play a major role, and unfortunately I, andmany others aren’t
aware of its benefits in totality.

Comments

This is a  very compact essay with good ideas. Here are a few general comments in << scientific content>>, [[tone,structure, organization]], and {{grammar}} to consider for future essays.I may have ADDED, or (removed) some words for the sake of completion, accuracy,or better flow.

[[need a title for your essay]]
 
 

 Minerals greatly affect the way that people live. From the smallest things
to the largest, minerals have probably played a rolein their formation and
existence  <<need to be more specific andassertive- words like 'things' and 'probably' make your sentence vagueand hesitant>>  .  In this course, I would like to know moreabout the specific
ways in which minerals contribute to our environmentand world <<good>>. [[paragraph break here-ened of introduction]]It would be
interesting to know what exact minerals make up a particular(thing) OBJECT (A thing
that we may look at everyday, but not know what it wasmade from).  It was
mentioned in class that the desks and chairs that weuse every day are made
(up) FROM of minerals.  There are many other itemsused in the world that are
important to society that people take for granted. Many think that they are
just what they are: a limestone bathtub, marble floorsand the gems in our
everyday jewelry etc.  However, they fail to realizethat they come from THE EARTH'S CRUST (a
much more natural places) AND MAY HAVE MANY OTHER APLICATIONS(as well as serve other purposes).  During the course
of this class, I would also like to know how mineralsare formed, the
difference between minerals and other natural substancesand the different
kinds of minerals <<GOOD>>.  It would be interestingto know what classifies
(something) A SUBSTANCE as A mineral and/or (the) ITSchemical COMPOSITION(make-up that it needs to have.)
This is important to me because minerals provide a worldfor me to live and
function in.  [[paragraph break here to start yourconclusion]]From the soil that I walk on to the air that I breath,
minerals play a major role, and unfortunately I, andmany others aren’t
aware of its benefits in totality.
 

{{Need to construct more definitive and more robust sentences.}}
[[Use paragraph breaks to divide your essay into threedistinct sections - introduction, body, and conclusion.  You havedone a good job in the contents of these sections, I just marked the paragraphbreaks for a better appearance and easier reading.]]
 

Essay

First Essay on Minerals

 I never take any science course in penn state beforeso when I first hear the word mineral in class I wasnít sure whatthat means. At first, I thought mineral comes from only plant.  Ididnít know exactly whatís the real definition for it. When you ask whatís itís made of mineral from plant, animal,or fossil thatís in the class thatís when I kind of understandabout mineral.
Minerals are very important to us in everyday life. Sometimes I used something that is mineral and I donít even noticeit.  Without mineral our life would be very hard. There wouldnítbe any house to stay, desk, chair, and etc.  There also wouldnítbe any electricity if there werenít any mineral.  I never knewthat until we talked about this during class.
 I want to learn how necklace, ring, and other jewelryare made of.  I know it is made of gold but I donít actuallyknow how is done.  By the end of this semester I would have a betterunderstanding of mineral.  I hope to acknowledge this and take otherscience classes.  My friend told me to take this emsc 121 becausehe told me that is very interesting and fun.  So far, I really likethis class and hope to learn some more fun stuff about minerals.
 

Comments

What you have here is not an essay, just a random collectionof some thoughts, or free writing.  You need to take these thoughtsadd more ideas and mold them into a essay structure that consists of introduction,main body, and conclusion.  You need to construct good sentences thatwill make up the paragraphs that are well connected throughout your essay. Make your essay tell an interesting story as you provide information. Here are a few general comments in << scientific content>>, [[tone,structure, organization]], and {{grammar}} to consider for future essays.
 
 

[[You need to have a professional tone in your essay anda good organization of the content.  You wrote this piece as if youwere talking to me.  That may be an interesting style for an essay,but you still need to have well-constructed, and grammatically correctsentences.  ]]

<<Give information that your readers would be interestedin; be more direct, and specific.>>

{{Need to work hard on your sentences; some are not clear,others don't stand by themselves, many need to be corrected for grammar.}}
 
 

First Essay on Minerals [[need a more inviting title]]

 I never take any science course in penn state beforeso when I first hear the word mineral in class I wasnít sure whatthat means. At first, I thought mineral comes from only plant.  Ididnít know exactly whatís the real definition for it. When you ask whatís itís made of mineral from plant, animal,or fossil thatís in the class thatís when I kind of understandabout mineral. <<Rewrite the previous three sentences to expressclearly what a mineral is, and is not.>>
Minerals are very important to us in everyday life. Sometimes I used something that is mineral and I donít even noticeit.  Without mineral our life would be very hard. There wouldnítbe any house to stay, desk, chair, and etc.  There also wouldnítbe any electricity <<why? Be more specific.  For example, without copper wire, how would electricity be transmitted. >> if there werenítany mineral.  I never knew that until we talked about this duringclass.
 I want to learn how necklace, ring, and other jewelryare made of.  I know it is made of gold but I donít actuallyknow how is done. [[I would put a paragraph break here to start the conclusionto  wrap up your essay in connection with  introduction, andthe body.]]  By the end of this semester I would have a better understandingof mineral.  I hope to acknowledge <<acknowledge may not bethe verb you are looking for here>> this and take other science classes. My friend told me to take this emsc 121 because he told me that is veryinteresting and fun <<because learning is fun, right?>>.  Sofar, I really like this class and hope to learn some more fun stuff aboutminerals.
 
 

Essay

 When someone first asks me to think of some thingsthat minerals are used for, only a few examples initially come to mind. Even though I'm not a girl, jewelry is usually the first for me and thenperhaps something like silverware or glass windows.  But after takingjust a few moments to really stop and think about all the different usesof minerals, I quickly realized that without minerals, I would be livinglike a caveman.
 Minerals are everywhere!  They are used inall sorts of everyday necessities from steel products, to chemicals, buildingmaterials, cars, fertilizers, and even electronics.  I then realizedthat all day long I am using minerals.  Wether it is directly or indirectly,minerals are a part of everything I do.  Going places in a car orplane requires steel made from Iron Ore....When I look at my watch to checkthe time, quartz is used in the components.  It then occurred to methat I should really be trying to think of something that is not made frommineral.  How about my clothes?  My T-shirt is made of cotton,which is a plant.  Sure this is true, but the machine used to makeit certainly wasn't made from a plant.  It was made from metallicminerals.
 I now had a goal of finding something that wasn'tmade with the help of a mineral, but first I could escape thinking aboutminerals for awhile and enjoy lunch.  Before I could bite into thatjuicy hamburger, images of a wire fence (made from metal) holding the cowsin the field came to mind.  Then I thought of the cows eating grainsand grasses that were grown with mineral rich fertilizers.  It becameclear to me that if you aren't using a mineral, you are most likely usingsomething that was made with the help of a mineral.  Wether it's buyinga soda with metal coins, or sleeping on a bed with a steel frame, I amusing minerals all the time, and I can't imagine my life without them.
 Throughout my education I have had only a coupleof science classes that touched on the subject of minerals.  Theseclasses had samples of different rocks and minerals and required the studentsto memorize them.  The next week, the students were then graded onhow many they could correctly identify.  I would expect this courseto devote some time in learning some of the common minerals and what theylook like.  This would be a good introduction, but certainly not themajor goal of the class.   Instead, I feel that learning wherelarge amounts of gold and diamonds could be found would be more important. If this isn't possible and you want to keep it a secret, then I would reallybe interested in what the newest minerals in todays society are and whatnew types of uses are being found for them.  Also, how are these mineralsmined? And finally, what is in store for the future when these naturalresources are exhausted?

Comments

This is a lively assay with good examples of how mineralsare weaved into the fabric of modern life.  Here are a few generalcomments in << scientific content>>, [[tone, structure, organization]],and {{grammar}} to consider for future essays. I may have ADDED, or (removed)some words for the sake of completion, accuracy, or better flow.
 

[[need a title]]

 (When someone first asks me to think of some thingsthat ) THINKING ABOUT WHAT minerals are used for, only a few examples (initially)come to mind (INITIALLY).  Even though I'm not a girl, jewelry isusually the first for me and then perhaps something like silverware orglass windows.  But after taking just a few moments to really stopand think about all the different uses of minerals, I quickly realizedthat without minerals, I would be living like a caveman <<you knowhow badly cave people  needed minerals for shelter, food, and defense>>.
 Minerals are everywhere!  They are used inall sorts of everyday necessities from steel products, to chemicals, buildingmaterials, cars, fertilizers, and even electronics.  I then realizedthat all day long I am using minerals.  Wether it is directly or indirectly,minerals are a part of everything I do.  Going places in a car orplane requires steel made from Iron Ore....When I look at my watch to checkthe time, quartz is used in the components.  It then occurred to methat I should really be trying to think of something that is not made frommineral.  How about my clothes?  My T-shirt is made of cotton,which is a plant.  Sure this is true, but the machine used to makeit certainly wasn't made from a plant.  It was made from metallicminerals.
 I now had a goal of finding something that wasn'tmade with the help of a mineral, but first I could escape thinking aboutminerals for awhile and enjoy lunch.  Before I could bite into thatjuicy hamburger, images of a wire fence (made from metal) holding the cowsin the field came to mind.  Then I thought of the cows eating grainsand grasses that were grown with mineral rich fertilizers.  It becameclear to me that if you aren't using a mineral, you are most likely usingsomething that was made with the help of a mineral.  Wether it's buyinga soda with metal coins, or sleeping on a bed with a steel frame, I amusing minerals all the time, and I can't imagine my life without them.
 Throughout my education I have had only a coupleof science classes that touched on the subject of minerals.  Theseclasses had samples of different rocks and minerals and required the studentsto memorize them.  The next week, the students were then graded onhow many they could correctly identify.  I would expect this courseto devote some time in learning some of the common minerals and what theylook like.  This would be a good introduction, but certainly not themajor goal of the class.   Instead, I feel that learning wherelarge amounts of gold and diamonds could be found would be more important. If this isn't possible and you want to keep it a secret, then I would reallybe interested in what the newest minerals in todays society are and whatnew types of uses are being found for them.  Also, how are these mineralsmined? And finally, what is in store for the future when these naturalresources are exhausted?
 

[[Good personal tone and a story thread running throughyour essay.  Good use of humor. You need to have a concluding paragraphto wrap up your essay]]

<<good, specific examples of  how mineralsare used in daily tasks and routines>>

Essay
 

First Essay on Minerals

 In nearly every aspect of my life there are mineralspresent.  From kicking rocks while

walking on concrete sidewalks to sitting in a brick buildingat a black stone desk, I notice minerals

in things that are around me.  What I did not realizewas the presence of minerals in electronics,

glass, the can I am sipping from, and half of the thingslying around my room. 

 Before I started this class, I had only thoughtof quarries when minerals came to mind since

there was a quarry near my house.  I could see theevidence when new foundations would be laid

in new houses, and in the layers of new road being putdown.  I never thought of metals as

minerals though.  To think that the fork I use ismade up of minerals went right over my head.  The

realization that copper in electronics and pipes or thetiny microprocessors in my computer were

mined out of the ground was something new to me.

 There is so much that can be made and discoveredfrom minerals that the possibilities are

endless.  What I want to get from this class is alook at how minerals are created and how they

are dispersed randomly around the world.  The readingtalked about how gold was the similar to

graphite or coal, but containing a different crystal structure. I want to learn how those tiny

differences that make such a big change in what the mineralsare.  Along that line, I would like to

learn about the different ways that minerals become present,like the volcano from 50 million years

ago versus a volcano out in the ring of fire. 

 Another idea that I have come upon is that therecould be minerals lying deep within the

earth that people have never seen before.  If ithas been 50 million years since the last kimberlitic

volcano, then what are the possibilities of another kindof volcano or a similar eruption today? 

 I have learned a little about plate tectonics. The major idea there that catches my eye is

how sea shells and things associated with the sea canbe found in mountains of the Himalayas,

and places such as Mt. Everest could be growing whileIndia might be getting smaller due to

tectonic plates pushing into each other.  More thananything, I am looking forward to learning about

minerals that are everywhere in the universe and havestories to tell.

Comments

This is a very interesting, and informative essay. Here are a few general comments in << scientific content>>, [[tone,structure, organization]], and {{grammar}} to consider for future essays.I may have ADDED, or (removed) some words for the sake of completion, accuracy,or better flow.

<<good information and good questions on the entirelife-cycle of minerals>>

[[good introduction, and good body text; need to workon conclusion to reflect on the whole essay.]]

{{ use simpler sentences with active voice, and try using'I' less frequently}}
 
 

First Essay on Minerals [[could use a more interestingtitle]]

 In nearly every aspect of my life there are mineralspresent.  From kicking rocks while

walking on concrete sidewalks to sitting in a brick buildingat a black stone desk, I notice THAT minerals

(in things that are around) SURROUND me [[use active voice]]. What I did not realize (was the presence of) THAT minerals WERE INVOLVEDin  MAKING electronic(s) DEVICES,

glass, the can I am sipping from, and half of the thingslying around my room. 

 Before I started this class, I had only thoughtof quarries when minerals came to mind since

there was a quarry near my house.  I could see theevidence when new foundations would be laid

in new houses, and in the layers of new road being putdown.  I never thought of metals as

minerals though.  To think that the fork I use ismade up of minerals went right over my head.  The

realization that copper in electronics and pipes or thetiny microprocessors in my computer were

mined out of the ground was something new to me.

 There is so much that can be made and discoveredfrom minerals that the possibilities are

endless.  What I want to get from this class is alook at how minerals are created and how they

are dispersed randomly around the world.  The readingtalked about how gold was the similar to

graphite or coal, but containing a different crystal structure. I want to learn how those tiny

differences that make such a big change in what the mineralsare.  Along that line, I would like to

learn about the different ways that minerals become present,like the volcano from 50 million years

ago versus a volcano out in the ring of fire. 

 Another idea that I have come upon is that therecould be minerals lying deep within the

earth that people have never seen before.  If ithas been 50 million years since the last kimberlitic

volcano, then what are the possibilities of another kindof volcano or a similar eruption today? 

 I have learned a little about plate tectonics. The major idea there that catches my eye is

how sea shells and things associated with the sea canbe found in mountains of the Himalayas,

and places such as Mt. Everest could be growing whileIndia might be getting smaller due to

tectonic plates pushing into each other.  More thananything, I am looking forward to learning about

minerals that are everywhere in the universe and havestories to tell.
 

Essay and Comments
 

This is a well-rounded and interesting essay.  Hereare a few general comments in << scientific content>>, [[tone, structure,organization]], and {{grammar}} to consider for future essays. I may haveADDED, or (removed) some words for the sake of completion, accuracy, orbetter flow.
 

<<Good references to different aspects of minerals:Properties, mining, environmental impact.    A wholisticapproach to the earth system.]]

[[well-organized essay with a healthy personal tone. Relate the concluding section more closely to the introduction and thebody of the essay. ]]

{{Try using active voice more frequently, and 'I' lessfrequently}}.
 
 

[[need a title]]
 

 When I hear the word "mineral", I usually thinkof
crystals or gemstones.  I love to collect quartz
crystals from all over the place, including some that
I have found right here in Pennsylvania.  I am
fascinated by the healing properties of various
crystals as well as their beautiful forms in clusters
or individually.  Unfortunately, my knowledge of
minerals is pretty limited at this point.  Sinceour
first class, I have started to take notice to just how
many things around me are made from or contain
minerals, and it is really amazing what a huge part
minerals play in my life [[good engaging introduction]].
 The [BROAD]range of useful minerals produced bythe earth( is
so broad,) AFFECT nearly every aspect of my life( isaffected
by them).  From fuel to jewelry, which I have an
enormous collection of, minerals (are all around) SURROUNDme and
I often fail to recognize them .  Hopefully, this
course will allow me to understand how humans have
learned to  USE (utilize) these wonderful giftsfrom the
earth, and also provide me with a better understanding
of the part I play in the whole system.  I am
interested in learning more about the environmental
issues surrounding mining of certain minerals and how
to help cut down on the environmental impact of
mining.  I strongly believe that we need to lookvery
closely at how our actions affect our ecosystems and
do whatever is necessary to preserve the earth for
those we share it with and for future generations. 
 I am actually looking forward to writing the term
paper, and have already decided that I would like to
write about quartz, because I find it so fascinating
and there is so much left for me to learn about it.
My knowledge of quartz is currently limited to its
spiritual and healing properties and I would like to
become more informed about the different types of
quartz, where they are found, and the many uses for it
other than healing.  Hopefully, my next mining trip
will be even more fulfilling as I will be much more
informed.
 

Essay and Comments

This is a well-constructed and well-written essay. Here are a few general comments in << scientific content>>, [[tone,structure, organization]], and {{grammar}} to consider for future essays.I may have ADDED, or (removed) some words for the sake of completion, accuracy,or better flow.

<<I appreciate your awareness of various environmentalproblems, and mineral industries certainly have their fair share of those, but none of the problems you list in your introduction is related to mineralindustries per se.  Try establishing good connections between topicsthat you cover.>>

[[Good organization of your ideas in well-constructedparagraphs.  Good incorporation of your daily routine with severalexamples of mineral uses. Good personal tone ]]

{{Good use of  simple, short sentences.  Tryusing 'I' less frequently.}}
 
 

Essay #1

Minerals affect everyone everyday in life. Many timeswe go through life’s daily routines not realizing how important MotherNature'S gifts are to us. Many of us live in a highly industrialized environmentand abuse the earth in many ways. Our cars create pollution, our hair spraydepletes the ozone layer, and we are constantly cutting down trees. TheUnited States wastes more resources then any other country when takinginto account populations. I for one, realize that minerals are very importantin our daily routines. For example, just observe my daily morning routine.

I start my morning off with a nice hot shower. But ifit weren’t for the silica it would be hard to keep the water hot. Afterwards,as every girl knows drying your hair can be a pain, because no one wantsto walk outside in 20 degree State College weather. If it wasn’t for thedifferent minerals inside the dryer then I wouldn’t endure <<endurethe luxury??>> the luxury of be able to use my blow dryer. Afterwards itstime to put my jewelry on. I especially love my gold and silver jewelry.I do not have too much gold, due to the cost of the particular mineral.Gold can be an expensive piece of jewelry. Afterwards its time to eat,I quickly microwave a bowl of oatmeal in a ceramic dish. Before I realizeit I have to catch the bus. I prefer the bus rather than driving to classbecause it is bigger and sturdier. It uses less fuel per person (then)THAN if everyone drove using his or her own car. Also I feel the bus issafer because of its many tons of steel. In my morning routine I must encounterat least 10 minerals, but those are only the ones I am aware of.

I wish to learn more about minerals and their importantrole in my life; that is why I am taking this class. Unfortunately, I donot know much about minerals, but I am willing to learn. Where do mineralscome from? Can we run out of particular specie of minerals? Can mineralsbe synthetically made? How often do I use minerals? These are just someof the many questions I have concerning minerals.

Prior to this class I would have to say my favorite mineralwould be a diamond. It is beautiful and has a lot of symbolism, but I amconfident that it is not the most useful mineral. I especially wish tolearn more about diamonds and gold. I believe I will be introduced to countlessnumbers of minerals that are just as intriguing and important.

Essay and Comments

Your essay is packed with many pieces of information andpersonal reflections.  I offer below a few general comments in <<scientific content>>, [[tone, structure, organization]], and {{grammar}}to consider for future essays.
 

<<Good reference to gemstone qualities of quartz,lead in glazes, use of salt as a deicer, silver, etc.   Regardingquartz, there is perhaps too much detail and use of technical terms thatshould be defined.  Don't assume that your readers are knowledgeablein  the topic you write about. >>

[[Good contextual incorporation of your major, and yourresidence in relation to various minerals to make personal reflections. Think about dividing your essay into three distinct sections; introduction,main body, and conclusion.  Your first paragraph is too long, combiningintroduction with the body. >>

{{Make shorter, and simpler sentences.  A few sentencesin your essay are too long, and can be broken down into three sentences!Try to use 'I' less frequently. }}
 
 

[[need an interesting title]]

                                    Although there are several ways that minerals affect my life that I amaware of, I feel that there must be a multitude of other instances of mineraluse in my life that I have never really thought about. Honestly, the firstthing that comes to my mind is my deepening fascination with jewelry, especiallygemstones. My birthstone is amethyst, a form of quartz, and since I canremember I have always loved jewelry made with this crystal. As my interestin gemstones has grown, I have picked up bits and pieces of informationhere and there regarding aspects such as their metamorphosis: for instanceI was never aware of the stone ametrine until I spoke with a gemstone dealeronce who informed me that under intense heat, citrine begins to tak! eon the properties of amethyst (I think!), since they are both forms ofquartz, forming ametrine.  Moreover, I am a big fan of silver jewelry.Besides jewelry though, minerals play an important role in my life consideringI travel a lot. I just recently spent a semester in Costa Rica doing volunteerwork (where there are some amazing rocks), and it took a large airplaneto get me there. I also drive a car, which uses petroleum products as wellas many minerals in its structure. As an Integrative Arts major, I havetaken classes in ceramics and pottery, and we always have to beware ofglazes containing lead, as well as utilize materials containing flourite. Anotherobvious mineral use is a product of my environment: coming from upstateNew York where there is a lot of snow, we need to salt the roads many timesa day most winters. Much of the salt that we use comes from the mine 10minutes from my house, at the bottom of Cayuga Lake in It! haca.
                Besides giving me an appreciation of more minerals and their uses otherthan in jewelry, I hope to learn  more about the formation of mineralsin this course. I am intrigued by how many people classisfy anything hardand on the ground as a "rock" when really it could be composed of materialscompletely different, and in a different way, than the rock beside it. Ialso am interested in the less strictly scientific uses of minerals andgemstones, as I know that many people believe in their holistic healingpowers; however, I  realize that I might need to take a differentcourse for that! Moreover, I look forward to understanding a little moreabout the Costa Rican environment (including the volcanoes) and the rocks& minerals found there, by applying what I have learned in EMSC 121.

Essay and Comments

Your essay is succinct, well-organized, and well-written. Just one comment:  Go to the last paragraph and rewrite all the sentencesthat  contain "as well  as."

Good job.
 

 When registering for this course, I had a very narrowknowledge of what minerals were. Besides knowing that minerals were containedin rocks, I really had never thought about what minerals were used forand where they come from.

 Since the first day of class, I have learned somethings that have sparked my interest. The fact that coal by some definitionsmay be considered a mineral is very interesting to me, having grown upin the heart of the coal region, in Shamokin, PA.
Shamokin and surrounding areas also had a large farmingcommunity where limestone from the local quarries was used as fertilizerfor the farmer‚s crops. At one time, and to some extent today everythingin my hometown revolved around minerals especially coal.
You can see how boroughs surrounding the city grew aroundthe old coalmines even today.

 Although I never looked into what coal or limestonewas composed of or whether it was a mineral, I could see how these mineralsaffected my life. As well as some of the application they were used for.In the upcoming semester I like to learn more about how these mineralsaffected the local economies and the lives of the people who worked inthese mines and quarries. As well as what other various minerals are usedfor in our everyday life, as well as where they come from and how theyare extracted from the earth.
 

Essay and Comments

Very good essay.  Good ideas,  good information,good organization,  and good English.   A few correctionsmarked in ALL CAPS.
 

How Minerals Affect My Life

        I never gavemuch thought as to what part minerals played in my life.  I nevereven thought of minerals.  Minerals to me were a kind of nutrientsin the earth that looked pretty and that was all I knew.  After thesefirst few days of class I have learned a new definition of what mineralsare, I know types of minerals and how they are produced, and I know waysin which they are used in everyday life.  I now see what an impactthe production of minerals has on our society and myself.
        Now I understandthat minerals are more than just rocks and stones.  They are inorganicsubstances that have great power to fuel cars, heat houses, insulate electricalwires, and ENABLE many other (things) TASKS.  (They) SINGLE METALSare mixed together to create strong metal(s) ALLOYS and (they) PRECIOUSMETALS are used alone as jewelry.  Without minerals much of our worldwould be different.
        Every daywhen I walk to class I walk over cement, rocks, and other types of walkways. Many of these walkways are made of minerals.  When I get up in themorning or before I go out I use eye shadow, made from a mineral calledmica.  When I get in my car (minerals) METALS called steel, manganese,and nickel create the safety cage around me and aluminum creates the shellaround that.  They are in the fuel and also there is platinum in thecatalyst of my exhaust.  When I get dressed up I put my silver orgold jewelry on, depending on what matches my outfit better.
Precious metals have been an important part of our culturefor many centuries.  Mining of minerals is also important to our economy. Because these minerals are in such demand the extraction of them from theground requires workers, thus creating jobs.  Minerals make many thingsstronger or more practical in our world.
        There aremany minerals and all of them are useful in some important way.  Mineralsclearly have a great impact on our industrialized world and will continueto in the future.
 

Essay
 

Minerals and Me

           Computers.  Television.  Music.  These are three of my favoritethings to do (outside of class of course) that make up part of my everydaylife.  After attending class these past few days, it has made me moreaware of how minerals affect me on a daily basis.  I have always havebeen amazed with the skill involved in developing the technology to makethe functioning of something as complicated as a computer or televisionpossible.  However, up until this point I have not had the knowledgeoutside of high school chemistry, I have not had the knowledge to discriminatethe c! ! haracteristic differences between one mineral and another. Minerals are a vital part of my life on a daily basis and without themand the skills to develop them into useful materials.

           There are many different minerals that go into making these items. The different characteristics of these minerals make it possible for themto serve different functions.  Things like copper, aluminum, coaland titanium are common minerals and elements that make these entertainmentoptions possible.  However, there are many questions that I hope toget answered as a result of taking this course.  Normally not a sciencefan, there are many scientific curiosities that I do have.  I wouldlike to learn how do I determine different physical properties of mineralsin terms of their possible uses in society.  After taking this course,I expect to have the knowledge to determine what minerals are used in othermaterials by looking at them.   The idea that so many items aredependent on mineral deposits is amazing.  It makes the complexityof our world seem more comprehensible to me.
 
 

Comments
 

Interesting essay with good ideas.  There is roomfor improvement in organization and sentence structures. Here are a fewgeneral comments in << scientific content>>, [[tone, structure, organization]],and {{grammar}} to consider for future essays. I have ADDED, or [removed]some words for the sake of completion, accuracy, or better flow of thetext.
 

Minerals and Me
 

          USING [C] computers[. ], WATCHING (T)television[. ], and LISTENING to [M]music[. These] are three of my favorite things to do (outside of class of course)[that make up part of my everyday life].  [After a]Attending classthese past few days [, it] has made me more aware of how minerals affectme on a daily basis.  I have always [have] been amazed with [the skillinvolved in developing] the technologIES[y] [to make the functioning ofsomething as complicated as a] THAT HAVE MADE computerS (or) AND televisionpossible.  However, up until this point I have not had the knowledgeoutside of high school chemistry, I have not had the knowledge to discriminatethe c! ! haracteristic differences between DIFFERENT MINERALS (one mineraland another).  Minerals [are] CONSTITUTE a vital part of my life ona daily basis and without them and the skills to develop them into usefulmaterials.{{incomplete sentence}}

           There are many different minerals that go into making these items {{Whichitems? Specify}}.  The different characteristics of these minerals{{which minerals?}} make it possible for them to serve different functions. Things like copper, aluminum, coal and titanium are common minerals andelements that make these {{which? not clear}} entertainment options possible. However, there are many questions that I hope to get answered as a resultof taking this course.  Normally not a science fan <<not a goodthing to say!>>, there are many scientific curiosities that I do have <<yes,of course you should.  I would like to learn how (do) I determinedifferent physical properties of minerals in terms of their possible usesin society.  [[paragraph break to start conclusion]]After taking thiscourse, I expect to have the knowledge to determine what minerals are usedin other materials by looking at them.   The idea that so manyitems are dependent on mineral deposits is amazing.  It makes thecomplexity of our world seem more comprehensible to me.
 
 

<<Good job pointing out the relationship betweenminerals and developing technologies.  Good reference to differencesbetween minerals in properties and applications.  Expression of curiosityin mineral composition.  Need to be more specific and clear in placesthat are marked in the text. >>
 

[[Need to organize your ideas clearly in three sectionsof the essay: introduction, body, and conclusion.  Could shorten introductionand strengthen conclusion. ]]

{{Watch your sentences, proofread carefully}}
 
 
 
 

For other uses, see Mineral (disambiguation).

A mineral is a naturally occurring chemical compound,[1] usually of crystalline form and abiogenic in origin (not produced by life processes). A mineral has one specific chemical composition, whereas a rock can be an aggregate of different minerals or mineraloids. The study of minerals is called mineralogy.

Each distinct type of mineral is also known as a mineral species.[note 1] As of March 2018[update], there are more than 5,500 known mineral species;[3] 5,312 of these have been approved by the International Mineralogical Association (IMA).[4]

Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various species, which were determined by the mineral's geological environment when formed. Changes in the temperature, pressure, or bulk composition of a rock mass cause changes in its minerals. Within a mineral species there may be variation in physical properties or minor amounts of impurities that are recognized by mineralogists or wider society as a mineral variety,[5] for example amethyst, a purple variety of the mineral species quartz.

Minerals can be described by their various physical properties, which are related to their chemical structure and composition. Common distinguishing characteristics include crystal structure and habit, hardness, lustre, diaphaneity, colour, streak, tenacity, cleavage, fracture, parting, specific gravity, magnetism, taste or smell, radioactivity, and reaction to acid.

Minerals are classified by key chemical constituents; the two dominant systems are the Dana classification and the Strunz classification. Silicon and oxygen constitute approximately 75% of the Earth's crust, which translates directly into the predominance of silicate minerals. The silicate minerals compose over 90% of the Earth's crust.[6] The silicate class of minerals is subdivided into six subclasses by the degree of polymerization in the chemical structure. All silicate minerals have a base unit of a [SiO4]4− silica tetrahedron—that is, a silicon cation coordinated by four oxygen anions, which gives the shape of a tetrahedron. These tetrahedra can be polymerized to give the subclasses: orthosilicates (no polymerization, thus single tetrahedra), disilicates (two tetrahedra bonded together), cyclosilicates (rings of tetrahedra), inosilicates (chains of tetrahedra), phyllosilicates (sheets of tetrahedra), and tectosilicates (three-dimensional network of tetrahedra). Other important mineral groups include the native elements, sulfides, oxides, halides, carbonates, sulfates, and phosphates.

Definition

Basic definition

One definition of a mineral encompasses the following criteria:[7]

  1. Formed by a natural process (anthropogenic compounds are excluded).
  2. Stable or metastable at room temperature (25 °C). In the simplest sense, this means the mineral must be solid. Classical examples of exceptions to this rule include native mercury, which crystallizes at −39 °C, and water ice, which is solid only below 0 °C; because these two minerals were described before 1959, they were grandfathered by the International Mineralogical Association (IMA).[8][9] Modern advances have included extensive study of liquid crystals, which also extensively involve mineralogy.
  3. Represented by a chemical formula. Minerals are chemical compounds, and as such they can be described by fixed or a variable formula. Many mineral groups and species are composed of a solid solution; pure substances are not usually found because of contamination or chemical substitution. For example, the olivine group is described by the variable formula (Mg, Fe)2SiO4, which is a solid solution of two end-member species, magnesium-rich forsterite and iron-rich fayalite, which are described by a fixed chemical formula. Mineral species themselves could have a variable compositions, such as the sulfide mackinawite, (Fe, Ni)9S8, which is mostly a ferrous sulfide, but has a very significant nickel impurity that is reflected in its formula.[7][10]
  4. Ordered atomic arrangement. This generally means crystalline, however, crystals are also periodic, so the broader criterion is used instead.[7] An ordered atomic arrangement gives rise to a variety of macroscopic physical properties, such as crystal form, hardness, and cleavage.[11] There have been several recent proposals to classify biogenic or amorphous substances as minerals. The formal definition of a mineral approved by the IMA in 1995: "A mineral is an element or chemical compound that is normally crystalline and that has been formed as a result of geological processes."[12]
  5. Usually abiogenic (not resulting from the activity of living organisms). Biogenic substances are explicitly excluded by the IMA: "Biogenic substances are chemical compounds produced entirely by biological processes without a geological component (e.g., urinary calculi, oxalate crystals in plant tissues, shells of marine molluscs, etc.) and are not regarded as minerals. However, if geological processes were involved in the genesis of the compound, then the product can be accepted as a mineral."[12]

The first three general characteristics are less debated than the last two.[7]

Recent advances

Mineral classification schemes and their definitions are evolving to match recent advances in mineral science. Recent changes have included the addition of an organic class, in both the new Dana and the Strunz classification schemes.[13][14] The organic class includes a very rare group of minerals with hydrocarbons. The IMA Commission on New Minerals and Mineral Names adopted in 2009 a hierarchical scheme for the naming and classification of mineral groups and group names and established seven commissions and four working groups to review and classify minerals into an official listing of their published names.[15][16] According to these new rules, "mineral species can be grouped in a number of different ways, on the basis of chemistry, crystal structure, occurrence, association, genetic history, or resource, for example, depending on the purpose to be served by the classification."[15]

The Nickel (1995)[clarification needed] exclusion of biogenic substances was not universally adhered to. For example, Lowenstam (1981) stated that "organisms are capable of forming a diverse array of minerals, some of which cannot be formed inorganically in the biosphere."[17] The distinction is a matter of classification and less to do with the constituents of the minerals themselves. Skinner (2005) views all solids as potential minerals and includes biominerals in the mineral kingdom, which are those that are created by the metabolic activities of organisms. Skinner expanded the previous definition of a mineral to classify "element or compound, amorphous or crystalline, formed through biogeochemical processes," as a mineral.[18]

Recent advances in high-resolution genetics and X-ray absorption spectroscopy are providing revelations on the biogeochemical relations between microorganisms and minerals that may make Nickel's (1995) biogenic mineral exclusion obsolete and Skinner's (2005) biogenic mineral inclusion a necessity.[12][18] For example, the IMA commissioned "Environmental Mineralogy and Geochemistry Working Group"[19] deals with minerals in the hydrosphere, atmosphere, and biosphere. The group's scope includes mineral-forming microorganisms, which exist on nearly every rock, soil, and particle surface spanning the globe to depths of at least 1600 metres below the sea floor and 70 kilometres into the stratosphere (possibly entering the mesosphere).[20][21][22]Biogeochemical cycles have contributed to the formation of minerals for billions of years. Microorganisms can precipitate metals from solution, contributing to the formation of ore deposits. They can also catalyze the dissolution of minerals.[23][24][25]

Prior to the International Mineralogical Association's listing, over 60 biominerals had been discovered, named, and published.[26] These minerals (a sub-set tabulated in Lowenstam (1981)[17]) are considered minerals proper according to the Skinner (2005) definition.[18] These biominerals are not listed in the International Mineral Association official list of mineral names,[27] however, many of these biomineral representatives are distributed amongst the 78 mineral classes listed in the Dana classification scheme.[18] Another rare class of minerals (primarily biological in origin) include the mineral liquid crystals that have properties of both liquids and crystals. To date over 80,000 liquid crystalline compounds have been identified.[28][29]

The Skinner (2005) definition of a mineral takes this matter into account by stating that a mineral can be crystalline or amorphous, the latter group including liquid crystals.[18] Although biominerals and liquid mineral crystals, are not the most common form of minerals,[30] they help to define the limits of what constitutes a mineral proper. The formal Nickel (1995) definition explicitly mentioned crystallinity as a key to defining a substance as a mineral. A 2011 article defined icosahedrite, an aluminium-iron-copper alloy as mineral; named for its unique natural icosahedral symmetry, it is a quasicrystal. Unlike a true crystal, quasicrystals are ordered but not periodic.[31][32]

Rocks, ores, and gems

Minerals are not equivalent to rocks. A rock is an aggregate of one or more minerals[33] or mineraloids. Some rocks, such as limestone or quartzite, are composed primarily of one mineral—calcite or aragonite in the case of limestone, and quartz in the latter case.[34][35] Other rocks can be defined by relative abundances of key (essential) minerals; a granite is defined by proportions of quartz, alkali feldspar, and plagioclase feldspar.[36] The other minerals in the rock are termed accessory, and do not greatly affect the bulk composition of the rock. Rocks can also be composed entirely of non-mineral material; coal is a sedimentary rock composed primarily of organically derived carbon.[33][37]

In rocks, some mineral species and groups are much more abundant than others; these are termed the rock-forming minerals. The major examples of these are quartz, the feldspars, the micas, the amphiboles, the pyroxenes, the olivines, and calcite; except the last one, all of the minerals are silicates.[38] Overall, around 150 minerals are considered particularly important, whether in terms of their abundance or aesthetic value in terms of collecting.[39]

Commercially valuable minerals and rocks are referred to as industrial minerals. For example, muscovite, a white mica, can be used for windows (sometimes referred to as isinglass), as a filler, or as an insulator.[40]Ores are minerals that have a high concentration of a certain element, typically a metal. Examples are cinnabar (HgS), an ore of mercury, sphalerite (ZnS), an ore of zinc, or cassiterite (SnO2), an ore of tin. Gems are minerals with an ornamental value, and are distinguished from non-gems by their beauty, durability, and usually, rarity. There are about 20 mineral species that qualify as gem minerals, which constitute about 35 of the most common gemstones. Gem minerals are often present in several varieties, and so one mineral can account for several different gemstones; for example, ruby and sapphire are both corundum, Al2O3.[41]

Nomenclature and classification

Minerals are classified by variety, species, series and group, in order of increasing generality. The basic level of definition is that of mineral species, each of which is distinguished from the others by unique chemical and physical properties. For example, quartz is defined by its formula, SiO2, and a specific crystalline structure that distinguishes it from other minerals with the same chemical formula (termed polymorphs). When there exists a range of composition between two minerals species, a mineral series is defined. For example, the biotite series is represented by variable amounts of the endmembersphlogopite, siderophyllite, annite, and eastonite. In contrast, a mineral group is a grouping of mineral species with some common chemical properties that share a crystal structure. The pyroxene group has a common formula of XY(Si,Al)2O6, where X and Y are both cations, with X typically bigger than Y; the pyroxenes are single-chain silicates that crystallize in either the orthorhombic or monoclinic crystal systems. Finally, a mineral variety is a specific type of mineral species that differs by some physical characteristic, such as colour or crystal habit. An example is amethyst, which is a purple variety of quartz.[42]

Two common classifications, Dana and Strunz, are used for minerals; both rely on composition, specifically with regards to important chemical groups, and structure. James Dwight Dana, a leading geologist of his time, first published his System of Mineralogy in 1837; as of 1997, it is in its eighth edition. The Dana classification assigns a four-part number to a mineral species. Its class number is based on important compositional groups; the type gives the ratio of cations to anions in the mineral; and the last two numbers group minerals by structural similarity within a given type or class. The less commonly used Strunz classification, named for German mineralogist Karl Hugo Strunz, is based on the Dana system, but combines both chemical and structural criteria, the latter with regards to distribution of chemical bonds.[43]

As of September 2017[update], 5,291 mineral species are approved by the IMA.[4] They are most commonly named after a person (45%), followed by discovery location (23%); names based on chemical composition (14%) and physical properties (8%) are the two other major groups of mineral name etymologies.[42][44] The common suffix -ite of mineral names descends from the ancient Greek suffix – ί τ η ς (-ites), meaning "connected with or belonging to".[45]

Chemistry

The abundance and diversity of minerals is controlled directly by their chemistry, in turn dependent on elemental abundances in the Earth. The majority of minerals observed are derived from the Earth's crust. Eight elements account for most of the key components of minerals, due to their abundance in the crust. These eight elements, summing to over 98% of the crust by weight, are, in order of decreasing abundance: oxygen, silicon, aluminium, iron, magnesium, calcium, sodium and potassium. Oxygen and silicon are by far the two most important – oxygen composes 47% of the crust by weight, and silicon accounts for 28%.[46]

The minerals that form are directly controlled by the bulk chemistry of the parent body. For example, a magma rich in iron and magnesium will form mafic minerals, such as olivine and the pyroxenes; in contrast, a more silica-rich magma will crystallize to form minerals that incorporate more SiO2, such as the feldspars and quartz. In a limestone, calcite or aragonite (both CaCO3) form because the rock is rich in calcium and carbonate. A corollary is that a mineral will not be found in a rock whose bulk chemistry does not resemble the bulk chemistry of a given mineral with the exception of trace minerals. For example, kyanite, Al2SiO5 forms from the metamorphism of aluminium-rich shales; it would not likely occur in aluminium-poor rock, such as quartzite.

The chemical composition may vary between end member species of a solid solution series. For example, the plagioclasefeldspars comprise a continuous series from sodium-rich end member albite (NaAlSi3O8) to calcium-rich anorthite (CaAl2Si2O8) with four recognized intermediate varieties between them (given in order from sodium- to calcium-rich): oligoclase, andesine, labradorite, and bytownite.[47] Other examples of series include the olivine series of magnesium-rich forsterite and iron-rich fayalite, and the wolframite series of manganese-rich hübnerite and iron-rich ferberite.

Chemical substitution and coordination polyhedra explain this common feature of minerals. In nature, minerals are not pure substances, and are contaminated by whatever other elements are present in the given chemical system. As a result, it is possible for one element to be substituted for another.[48] Chemical substitution will occur between ions of a similar size and charge; for example, K+ will not substitute for Si4+ because of chemical and structural incompatibilities caused by a big difference in size and charge. A common example of chemical substitution is that of Si4+ by Al3+, which are close in charge, size, and abundance in the crust. In the example of plagioclase, there are three cases of substitution. Feldspars are all framework silicates, which have a silicon-oxygen ratio of 2:1, and the space for other elements is given by the substitution of Si4+ by Al3+ to give a base unit of [AlSi3O8]; without the substitution, the formula would be charge-balanced as SiO2, giving quartz.[49] The significance of this structural property will be explained further by coordination polyhedra. The second substitution occurs between Na+ and Ca2+; however, the difference in charge has to accounted for by making a second substitution of Si4+ by Al3+.[50]

Coordination polyhedra are geometric representation of how a cation is surrounded by an anion. In mineralogy, coordination polyhedra are usually considered in terms of oxygen, due its abundance in the crust. The base unit of silicate minerals is the silica tetrahedron – one Si4+ surrounded by four O2−. An alternate way of describing the coordination of the silicate is by a number: in the case of the silica tetrahedron, the silicon is said to have a coordination number of 4. Various cations have a specific range of possible coordination numbers; for silicon, it is almost always 4, except for very high-pressure minerals where compound is compressed such that silicon is in six-fold (octahedral) coordination by oxygen. Bigger cations have a bigger coordination number because of the increase in relative size as compared to oxygen (the last orbital subshell of heavier atoms is different too). Changes in coordination numbers between leads to physical and mineralogical differences; for example, at high pressure such as in the mantle, many minerals, especially silicates such as olivine and garnet will change to a perovskite structure, where silicon is in octahedral coordination. Another example are the aluminosilicates kyanite, andalusite, and sillimanite (polymorphs, as they share the formula Al2SiO5), which differ by the coordination number of the Al3+; these minerals transition from one another as a response to changes in pressure and temperature.[46] In the case of silicate materials, the substitution of Si4+ by Al3+ allows for a variety of minerals because of the need to balance charges.[51]

Changes in temperature and pressure, and composition alter the mineralogy of a rock sample. Changes in composition can be caused by processes such as weathering or metasomatism (hydrothermal alteration). Changes in temperature and pressure occur when the host rock undergoes tectonic or magmatic movement into differing physical regimes. Changes in thermodynamic conditions make it favourable for mineral assemblages to react with each other to produce new minerals; as such, it is possible for two rocks to have an identical or a very similar bulk rock chemistry without having a similar mineralogy. This process of mineralogical alteration is related to the rock cycle. An example of a series of mineral reactions is illustrated as follows.[52]

Orthoclase feldspar (KAlSi3O8) is a mineral commonly found in granite, a plutonicigneous rock. When exposed to weathering, it reacts to form kaolinite (Al2Si2O5(OH)4, a sedimentary mineral, and silicic acid):

2 KAlSi3O8 + 5 H2O + 2 H+ → Al2Si2O5(OH)4 + 4 H2SiO3 + 2 K+

Under low-grade metamorphic conditions, kaolinite reacts with quartz to form pyrophyllite (Al2Si4O10(OH)2):

Al2Si2O5(OH)4 + SiO2 → Al2Si4O10(OH)2 + H2O

As metamorphic grade increases, the pyrophyllite reacts to form kyanite and quartz:

Al2Si4O10(OH)2 → Al2SiO5 + 3 SiO2 + H2O

Alternatively, a mineral may change its crystal structure as a consequence of changes in temperature and pressure without reacting. For example, quartz will change into a variety of its SiO2polymorphs, such as tridymite and cristobalite at high temperatures, and coesite at high pressures.[53]

Physical properties

Classifying minerals ranges from simple to difficult. A mineral can be identified by several physical properties, some of them being sufficient for full identification without equivocation. In other cases, minerals can only be classified by more complex optical, chemical or X-ray diffraction analysis; these methods, however, can be costly and time-consuming. Physical properties applied for classification include crystal structure and habit, hardness, lustre, diaphaneity, colour, streak, cleavage and fracture, and specific gravity. Other less general tests include fluorescence, phosphorescence, magnetism, radioactivity, tenacity (response to mechanical induced changes of shape or form), piezoelectricity and reactivity to dilute acids.[54]

Crystal structure and habit

Main articles: Crystal system and Crystal habit

See also: Crystal twinning

Crystal structure results from the orderly geometric spatial arrangement of atoms in the internal structure of a mineral. This crystal structure is based on regular internal atomic or ionic arrangement that is often expressed in the geometric form that the crystal takes. Even when the mineral grains are too small to see or are irregularly shaped, the underlying crystal structure is always periodic and can be determined by X-ray diffraction.[7] Minerals are typically described by their symmetry content. Crystals are restricted to 32 point groups, which differ by their symmetry. These groups are classified in turn into more broad categories, the most encompassing of these being the six crystal families.[55]

These families can be described by the relative lengths of the three crystallographic axes, and the angles between them; these relationships correspond to the symmetry operations that define the narrower point groups. They are summarized below; a, b, and c represent the axes, and α, β, γ represent the angle opposite the respective crystallographic axis (e.g. α is the angle opposite the a-axis, viz. the angle between the b and c axes):[55]

Crystal familyLengthsAnglesCommon examples
Isometrica=b=cα=β=γ=90°Garnet, halite, pyrite
Tetragonala=b≠cα=β=γ=90°Rutile, zircon, andalusite
Orthorhombica≠b≠cα=β=γ=90°Olivine, aragonite, orthopyroxenes
Hexagonala=b≠cα=β=90°, γ=120°Quartz, calcite, tourmaline
Monoclinica≠b≠cα=γ=90°, β≠90°Clinopyroxenes, orthoclase, gypsum
Triclinica≠b≠cα≠β≠γ≠90°Anorthite, albite, kyanite

The hexagonal crystal family is also split into two crystal systems – the trigonal, which has a three-fold axis of symmetry, and the hexagonal, which has a six-fold axis of symmetry.

Chemistry and crystal structure together define a mineral. With a restriction to 32 point groups, minerals of different chemistry may have identical crystal structure. For example, halite (NaCl), galena (PbS), and periclase (MgO) all belong to the hexaoctahedral point group (isometric family), as they have a similar stoichiometry between their different constituent elements. In contrast, polymorphs are groupings of minerals that share a chemical formula but have a different structure. For example, pyrite and marcasite, both iron sulfides, have the formula FeS2; however, the former is isometric while the latter is orthorhombic. This polymorphism extends to other sulfides with the generic AX2 formula; these two groups are collectively known as the pyrite and marcasite groups.[56]

Polymorphism can extend beyond pure symmetry content. The aluminosilicates are a group of three minerals – kyanite, andalusite, and sillimanite – which share the chemical formula Al2SiO5. Kyanite is triclinic, while andalusite and sillimanite are both orthorhombic and belong to the dipyramidal point group. These difference arise correspond to how aluminium is coordinated within the crystal structure. In all minerals, one aluminium ion is always in six-fold coordination by oxygen; the silicon, as a general rule is in four-fold coordination in all minerals; an exception is a case like stishovite (SiO2, an ultra-high pressure quartz polymorph with rutile structure).[57] In kyanite, the second aluminium is in six-fold coordination; its chemical formula can be expressed as Al[6]Al[6]SiO5, to reflect its crystal structure. Andalusite has the second aluminium in five-fold coordination (Al[6]Al[5]SiO5) and sillimanite has it in four-fold coordination (Al[6]Al[4]SiO5).[58]

Differences in crystal structure and chemistry greatly influence other physical properties of the mineral. The carbon allotropes diamond and graphite have vastly different properties; diamond is the hardest natural substance, has an adamantine lustre, and belongs to the isometric crystal family, whereas as graphite is very soft, has a greasy lustre, and crystallises in the hexagonal family. This difference is accounted by differences in bonding. In diamond, the carbons are in sp3 hybrid orbitals, which means they form a framework where each carbon is covalently bonded to four neighbours in a tetrahedral fashion; on the other hand, graphite is composed of sheets of carbons in sp2 hybrid orbitals, where each carbon is bonded covalently to only three others. These sheets are held together by much weaker van der Waals forces, and this discrepancy translates to big macroscopic differences.[59]

Twinning is the intergrowth of two or more crystal of a single mineral species. The geometry of the twinning is controlled by the mineral's symmetry. As a result, there are several types of twins, including contact twins, reticulated twins, geniculated twins, penetration twins, cyclic twins, and polysynthetic twins. Contact, or simple twins, consist of two crystals joined at a plane; this type of twinning is common in spinel. Reticulated twins, common in rutile, are interlocking crystals resembling netting. Geniculated twins have a bend in the middle that is caused by start of the twin. Penetration twins consist of two single crystals that have grown into each other; examples of this twinning include cross-shaped staurolite twins and Carlsbad twinning in orthoclase. Cyclic twins are caused by repeated twinning around a rotation axis. It occurs around three, four, five, six, or eight-fold axes, and the corresponding patterns are called threelings, fourlings, fivelings, sixlings, and eightlings. Sixlings are common in aragonite. Polysynthetic twins are similar to cyclic twinning by the presence of repetitive twinning; however, instead of occurring around a rotational axis, it occurs along parallel planes, usually on a microscopic scale.[60][61]

Crystal habit refers to the overall shape of crystal. Several terms are used to describe this property. Common habits include acicular, which described needlelike crystals like in natrolite, bladed, dendritic (tree-pattern, common in native copper), equant, which is typical of garnet, prismatic (elongated in one direction), and tabular, which differs from bladed habit in that the former is platy whereas the latter has a defined elongation. Related to crystal form, the quality of crystal faces is diagnostic of some minerals, especially with a petrographic microscope. Euhedral crystals have a defined external shape, while anhedral crystals do not; those intermediate forms are termed subhedral.[62][63]

Hardness

Main article: Mohs scale of mineral hardness

The hardness of a mineral defines how much it can resist scratching. This physical property is controlled by the chemical composition and crystalline structure of a mineral. A mineral's hardness is not necessarily constant for all sides, which is a function of its structure; crystallographic weakness renders some directions softer than others.[64] An example of this property exists in kyanite, which has a Mohs hardness of 5½ parallel to [001] but 7 parallel to [100].[65]

The most common scale of measurement is the ordinal Mohs hardness scale. Defined by ten indicators, a mineral with a higher index scratches those below it. The scale ranges from talc, a phyllosilicate, to diamond, a carbon polymorph that is the hardest natural material. The scale is provided below:[64]

Lustre and diaphaneity

Main article: Lustre (mineralogy)

Lustre indicates how light reflects from the mineral's surface, with regards to its quality and intensity. There are numerous qualitative terms used to describe this property, which are split into metallic and non-metallic categories. Metallic and sub-metallic minerals have high reflectivity like metal; examples of minerals with this lustre are galena and pyrite. Non-metallic lustres include: adamantine, such as in diamond; vitreous, which is a glassy lustre very common in silicate minerals; pearly, such as in talc and apophyllite, resinous, such as members of the garnet group, silky which common in fibrous minerals such as asbestiform chrysotile.[66]

The diaphaneity of a mineral describes the ability of light to pass through it. Transparent minerals do not diminish the intensity of light passing through it. An example of such a mineral is muscovite (potassium mica); some varieties are sufficiently clear to have been used for windows. Translucent minerals allow some light to pass, but less than those that are transparent. Jadeite and nephrite (mineral forms of jade are examples of minerals with this property). Minerals that do not allow light to pass are called opaque.[67][68]

The diaphaneity of a mineral depends on thickness of the sample. When a mineral is sufficiently thin (e.g., in a thin section for petrography), it may become transparent even if that property is not seen in hand sample. In contrast, some minerals, such as hematite or pyrite are opaque even in thin-section.[68]

Colour and streak

Main article: Streak (mineralogy)

Colour is the most obvious property of a mineral, but it is often non-diagnostic.[69] It is caused by electromagnetic radiation interacting with electrons (except in the case of incandescence, which does not apply to minerals).[70] Two broad classes of elements (idiochromatic and allochromatic) are defined with regards to their contribution to a mineral's colour: Idiochromatic elements are essential to a mineral's composition; their contribution to a mineral's colour is diagnostic.[67][71] Examples of such minerals are malachite (green) and azurite (blue). In contrast, allochromatic elements in minerals are present in trace amounts as impurities. An example of such a mineral would be the ruby and sapphire varieties of the mineral corundum.[71] The colours of pseudochromatic minerals are the result of interference of light waves. Examples include labradorite and bornite.

In addition to simple body colour, minerals can have various other distinctive optical properties, such as play of colours, asterism, chatoyancy, iridescence, tarnish, and pleochroism. Several of these properties involve variability in colour. Play of colour, such as in opal, results in the sample reflecting different colours as it is turned, while pleochroism describes the change in colour as light passes through a mineral in a different orientation. Iridescence is a variety of the play of colours where light scatters off a coating on the surface of crystal, cleavage planes, or off layers having minor gradations in chemistry.[72] In contrast, the play of colours in opal is caused by light refracting from ordered microscopic silica spheres within its physical structure.[73] Chatoyancy ("cat's eye") is the wavy banding of colour that is observed as the sample is rotated; asterism, a variety of chatoyancy, gives the appearance of a star on the mineral grain. The latter property is particularly common in gem-quality corundum.[72][73]

The streak of a mineral refers to the colour of a mineral in powdered form, which may or may not be identical to its body colour.[71] The most common way of testing this property is done with a streak plate, which is made out of porcelain and coloured either white or black. The streak of a mineral is independent of trace elements[67] or any weathering surface.[71] A common example of this property is illustrated with hematite, which is coloured black, silver, or red in hand sample, but has a cherry-red[67] to reddish-brown streak.[71] Streak is more often distinctive for metallic minerals, in contrast to non-metallic minerals whose body colour is created by allochromatic elements.[67] Streak testing is constrained by the hardness of the mineral, as those harder than 7 powder the streak plate instead.[71]

Cleavage, parting, fracture, and tenacity

Main articles: Cleavage (crystal) and Fracture (mineralogy)

By definition, minerals have a characteristic atomic arrangement. Weakness in this crystalline structure causes planes of weakness, and the breakage of a mineral along such planes is termed cleavage. The quality of cleavage can be described based on how cleanly and easily the mineral breaks; common descriptors, in order of decreasing quality, are "perfect", "good", "distinct", and "poor". In particularly transparent mineral, or in thin-section, cleavage can be seen a series of parallel lines marking the planar surfaces when viewed at a side. Cleavage is not a universal property among minerals; for example, quartz, consisting of extensively interconnected silica tetrahedra, does not have a crystallographic weakness which would allow it to cleave. In contrast, micas, which have perfect basal cleavage, consist of sheets of silica tetrahedra which are very weakly held together.[74][75]

As cleavage is a function of crystallography, there are a variety of cleavage types. Cleavage occurs typically in either one, two, three, four, or six directions. Basal cleavage in one direction is a distinctive property of the micas. Two-directional cleavage is described as prismatic, and occurs in minerals such as the amphiboles and pyroxenes. Minerals such as galena or halite have cubic (or isometric) cleavage in three directions, at 90°; when three directions of cleavage are present, but not at 90°, such as in calcite or rhodochrosite, it is termed rhombohedral cleavage. Octahedral cleavage (four directions) is present in fluorite and diamond, and sphalerite has six-directional dodecahedral cleavage.[74][75]

Minerals with many cleavages might not break equally well in all of the directions; for example, calcite has good cleavage in three direction, but gypsum has perfect cleavage in one direction, and poor cleavage in two other directions. Angles between cleavage planes vary between minerals. For example, as the amphiboles are double-chain silicates and the pyroxenes are single-chain silicates, the angle between their cleavage planes is different. The pyroxenes cleave in two directions at approximately 90°, whereas the amphiboles distinctively cleave in two directions separated by approximately 120° and 60°. The cleavage angles can be measured with a contact goniometer, which is similar to a protractor.[74][75]

Parting, sometimes called "false cleavage", is similar in appearance to cleavage but is instead produced by structural defects in the mineral as opposed to systematic weakness. Parting varies from crystal to crystal of a mineral, whereas all crystals of a given mineral will cleave if the atomic structure allows for that property. In general, parting is caused by some stress applied to a crystal. The sources of the stresses include deformation (e.g. an increase in pressure), exsolution, or twinning. Minerals that often display parting include the pyroxenes, hematite, magnetite, and corundum.[74][76]

When a mineral is broken in a direction that does not correspond to a plane of cleavage, it is termed to have been fractured. There are several types of uneven fracture. The classic example is conchoidal fracture, like that of quartz; rounded surfaces are created, which are marked by smooth curved lines. This type of fracture occurs only in very homogeneous minerals. Other types of fracture are fibrous, splintery, and hackly. The latter describes a break along a rough, jagged surface; an example of this property is found in native copper.[77]

Tenacity is related to both cleavage and fracture. Whereas fracture and cleavage describes the surfaces that are created when a mineral is broken, tenacity describes how resistant a mineral is to such breaking. Minerals can be described as brittle, ductile, malleable, sectile, flexible, or elastic.[78]

Specific gravity

Specific gravity numerically describes the density of a mineral. The dimensions of density are mass divided by volume with units: kg/m3 or g/cm3. Specific gravity measures how much water a mineral sample displaces. Defined as the quotient of the mass of the sample and difference between the weight of the sample in air and its corresponding weight in water, specific gravity is a unitless ratio. Among most minerals, this property is not diagnostic. Rock forming minerals – typically silicates or occasionally carbonates – have a specific gravity of 2.5–3.5.[79]

High specific gravity is a diagnostic property of a mineral. A variation in chemistry (and consequently, mineral class) correlates to a change in specific gravity. Among more common minerals, oxides and sulfides tend to have a higher specific gravity as they include elements with higher atomic mass. A generalization is that minerals with metallic or adamantine lustre tend to have higher specific gravities than those having a non-metallic to dull lustre. For example, hematite, Fe2O3, has a specific gravity of 5.26[80] while galena, PbS, has a specific gravity of 7.2–7.6,[81] which is a result of their high iron and lead content, respectively. A very high specific gravity becomes very pronounced in native metals; kamacite, an iron-nickel alloy common in iron meteorites has a specific gravity of 7.9,[82] and gold has an observed specific gravity between 15 and 19.3.[79][83]

Other properties

Other properties can be used to diagnose minerals. These are less general, and apply to specific minerals.

Dropping dilute acid (often 10% HCl) aids in distinguishing carbonates from other mineral classes. The acid reacts with the carbonate ([CO3]2−) group, which causes the affected area to effervesce, giving off carbon dioxide gas. This test can be further expanded to test the mineral in its original crystal form or powdered. An example of this test is done when distinguish calcite from dolomite, especially within rocks (limestone and dolostone respectively). Calcite immediately effervesces in acid, whereas acid must be applied to powdered dolomite (often to a scratched surface in a rock), for it to effervesce.[84]Zeolite minerals will not effervesce in acid; instead, they become frosted after 5–10 minutes, and if left in acid for a day, they dissolve or become a silica gel.[85]

When tested, magnetism is a very conspicuous property of minerals. Among common minerals, magnetite exhibits this property strongly, and it is also present, albeit not as strongly, in pyrrhotite and ilmenite.[84] Some minerals exhibit electrical properties – for example, quartz is piezoelectric – but electrical properties are rarely used as diagnostic criteria for minerals because of incomplete data and natural variation.[86]

Minerals can also be tested for taste or smell. Halite, NaCl, is table salt; its potassium-bearing counterpart, sylvite, has a pronounced bitter taste. Sulfides have a characteristic smell, especially as samples are fractured, reacting, or powdered.[84]

Radioactivity is a rare property; minerals may be composed of radioactive elements. They could be a defining constituent, such as uranium in uraninite, autunite, and carnotite, or as trace impurities. In the latter case, the decay of a radioactive element damages the mineral crystal; the result, termed a radioactive halo or pleochroic halo, is observable by various techniques, such as thin-section petrography.[84]

Classification

As the composition of the Earth's crust is dominated by silicon and oxygen, silicate elements are by far the most important class of minerals in terms of rock formation and diversity. However, non-silicate minerals are of great economic importance, especially as ores.[87][88]

Non-silicate minerals are subdivided into several other classes by their dominant chemistry, which included native elements, sulfides, halides, oxides and hydroxides, carbonates and nitrates, borates, sulfates, phosphates, and organic compounds. Most non-silicate mineral species are rare (constituting in total 8% of the Earth's crust), although some are relatively common, such as calcite, pyrite, magnetite, and hematite. There are two major structural styles observed in non-silicates: close-packing and silicate-like linked tetrahedra. The close-packed structures, which is a way to densely pack atoms while minimizing interstitial space. Hexagonal close-packing involves stacking layers where every other layer is the same ("ababab"), whereas cubic close-packing involves stacking groups of three layers ("abcabcabc"). Analogues to linked silica tetrahedra include SO4 (sulfate), PO4 (phosphate), AsO4 (arsenate), and VO4 (vanadate). The non-silicates have great economic importance, as they concentrate elements more than the silicate minerals do.[89]

The largest grouping of minerals by far are the silicates; most rocks are composed of greater than 95% silicate minerals, and over 90% of the Earth's crust is composed of these minerals.[90] The two main constituents of silicates are silicon and oxygen, which are the two most abundant elements in the Earth's crust. Other common elements in silicate minerals correspond to other common elements in the Earth's crust, such aluminium, magnesium, iron, calcium, sodium, and potassium.[91] Some important rock-forming silicates include the feldspars, quartz, olivines, pyroxenes, amphiboles, garnets, and micas.

Silicates

Main article: Silicate minerals

The base of unit of a silicate mineral is the [SiO4]4− tetrahedron. In the vast majority of cases, silicon is in four-fold or tetrahedral coordination with oxygen. In very high-pressure situations, silicon will be six-fold or octahedral coordination, such as in the perovskite structure or the quartz polymorph stishovite (SiO2). In the latter case, the mineral no longer has a silicate structure, but that of rutile (TiO2), and its associated group, which are simple oxides. These silica tetrahedra are then polymerized to some degree to create various structures, such as one-dimensional chains, two-dimensional sheets, and three-dimensional frameworks. The basic silicate mineral where no polymerization of the tetrahedra has occurred requires other elements to balance out the base 4- charge. In other silicate structures, different combinations of elements are required to balance out the resultant negative charge. It is common for the Si4+ to be substituted by Al3+ because of similarity in ionic radius and charge; in those case, the [AlO4]5− tetrahedra form the same structures as do the unsubstituted tetrahedra, but their charge-balancing requirements are different.[92]

The degree of polymerization can be described by both the structure formed and how many tetrahedral corners (or coordinating oxygens) are shared (for aluminium and silicon in tetrahedral sites).[93] Orthosilicates (or nesosilicates) have no linking of polyhedra, thus tetrahedra share no corners. Disilicates (or sorosilicates) have two tetrahedra sharing one oxygen atom. Inosilicates are chain silicates; single-chain silicates have two shared corners, whereas double-chain silicates have two or three shared corners. In phyllosilicates, a sheet structure is formed which requires three shared oxygens; in the case of double-chain silicates, some tetrahedra must share two corners instead of three as otherwise a sheet structure would result. Framework silicates, or tectosilicates, have tetrahedra that share all four corners. The ring silicates, or cyclosilicates, only need tetrahedra to share two corners to form the cyclical structure.[94]

The silicate subclasses are described below in order of decreasing polymerization.

Tectosilicates

Tectosilicates, also known as framework silicates, have the highest degree of polymerization. With all corners of a tetrahedra shared, the silicon:oxygen ratio becomes 1:2. Examples are quartz, the feldspars, feldspathoids, and the zeolites. Framework silicates tend to be particularly chemically stable as a result of strong covalent bonds.[95]

Forming 12% of the Earth's crust, quartz (SiO2) is the most abundant mineral species. It is characterized by its high chemical and physical resistivity. Quartz has several polymorphs, including tridymite and cristobalite at high temperatures, high-pressure coesite, and ultra-high pressure stishovite

Hübnerite, the manganese-rich end-member of the wolframite series, with minor quartz in the background
When minerals react, the products will sometimes assume the shape of the reagent; the product mineral is termed a pseudomorph of (or after) the reagent. Illustrated here is a pseudomorph of kaolinite after orthoclase. Here, the pseudomorph preserved the Carlsbad twinning common in orthoclase.
Topaz has a characteristic orthorhombic elongated crystal shape.
Contact twins, as seen in spinel
Diamond is the hardest natural material, and has a Mohs hardness of 10.

Colour is typically not a diagnostic property of minerals. Shown are green uvarovite (left) and red-pink grossular (right), both garnets. The diagnostic features would include dodecahedral crystals, resinous lustre, and hardness around 7.

Perfect basal cleavage as seen in biotite (black), and good cleavage seen in the matrix (pink orthoclase).
Galena, PbS, is a mineral with a high specific gravity.
Carnotite (yellow) is a radioactive uranium-bearing mineral.
Aegirine, an iron-sodium clinopyroxene, is part of the inosilicate subclass.
Natrolite is a mineral series in the zeolite group; this sample has a very prominent acicular crystal habit.
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