rocks! important! answers needed for tests!?
479025
Metamorphic rocks are already existing rocks that change under heat, pressure or in chemical reactions (usually underground). Examples are Gneiss (that froms from Granite), Slate (formed from Shale), and Quartzite (formed from Sandstone).\n\nSedimentary rocks are rocks made from sediment (haha makes sense, no?) which can be both organic (fossils!) or inorganic. They are formed into a solid rock through a variety of different forces, including erosion, deposition, compaction, and cementation. There are 3 major groups of sedimentary rocks, which are clastic (formed from the compression of rock fragments), organic rocks (Key word: ORGANIC, aka the remains of plants and animals), and chemical rocks (formed when a solution dissolves, & minerals are left behind). Examples:\nClastic: Shale, Sandstone, Conglomerate, and Breecia\nOrganic: Coal, Limestone\nChemical: Halite, Gypsum\n\nIgneous rocks are formed from magma or lava. They are classifed according to where they were formed-- extrusive rocks are formed from lava on Earth's surface, while intrusive rocks are formed from hardened magma beneath Earth's surface. Texture and mineral composition are also factors of classification. Examples include granite (which is extremely abundant), Rhyolite, Pegmatite, Porphyry, Basalt, Pumice, and Obsidian.
735831
Did you put your entire homework assignment on here? I noticed you posted a bunch of science questions just now.\nIf you don't have your textbook handy [you really should be looking up these answers so that you can remember and understand them when you have your test/exam], go to the links below and look them up. The 1st is a down loadable physics textbook. The 2nd has animations of physics.
96253
Calcite...my favorite mineral!!! (Calcium carbonate, get it?)\n\nHardness is the most obvious. Calcite is 3 on Moh's scale. Quite soft! and quartz is 7.\n\nA penny, a nail or knife, a glass plate, all will help you separate these two. The quartz will scratch everything there. \n\nOne more test, that I didn't put on your other list that is the best test here, the acid test. A dilute acid will fizz when applied to the calcite, while the quartz will not react at all. This is why all good geologists carry around a bottle of acid in the field. Quartz (sandstone) and calcite (limestone) can be deceptively similar in appearance. \n\nThese two are good examples of why you cannot rely on just color or shape. Both quartz and calcite come in a variety of colors, depending on the impurity, and both can be completely opaque.(Think of rose quartz, milky quartz, amethyst, etc, and realize that calcite has as much variety) Both can be very similar crystal shapes since they are both in the trigonal system. Both have a white streak. Both have a glassy (vitreous) luster. \nCalcite:\nhttp://webmineral.com/data/Calcite.shtml\nQuartz:\nhttp://webmineral.com/data/Quartz.shtml\n\nThere is one more online resource I think you should look at:http://www.mindat.org/\nWebmineral.com is better for the questions you have asked, but mindat.org is very comprehensive and will have photos of more variations of the minerals that might help you understand the challenge of picking which properties are best for which minerals. On a lab test, you may be given samples to test that you have never seen, and they may be minerals you have seen before but in a different form (yes- its a trick), so knowing your tests can save you.\n\nBy the way, I just noticed your question about why color should be used with caution for identifying minerals. I think this answer is a good example of that. Many minerals come in many different colors due to some small impurity in the mineral. Both quartz and calcite come in almost every color of the rainbow. Fluorite is another good example of a mineral that can come in many different colors. Other examples are the many copper compounds which come in various shades of blues and greens. Because there are so many different copper minerals with the same color you can't use the color as a diagnostic for any one of them.
746667
I don't know how to explain why we go in different directions in life, but rocks and minerals were always an interest to me. I love the outdoors, and prospecting. Knowledge of both and enjoying what you do makes it nice in life.
634548
Rocks can be divided into three key different groups, which you will need to know for chemistry and geography exams.\n\nThey are:\n- igneous\ne.g. volcanic rocks\n\n- sedimentary\ne.g. those laid down by the action of water, like limestone\n\n- metamorphic\ne.g. those that have been subject to many different processes within the earth and been changed as a result
490855
rock \nIt doesn't sound the same all the time
786248
dairydahm is right!  It's conglomerate.  Sedimentary (so you were right, too) rocks can contain pebbles of similar or varying sizes, depending where it formed.  Below are some sites that have pics of conglomerates for you to check--if you don't believe us.  (I'm a geology teacher, by the way.  (-; )
503979
Hey! tht wasan easy exam this yr.. even i gave it.... u will not get the answers anywhere thy r not out so soon.. Best Of Luck
334845
Skip geology class?...j/k\n\nhere's a link to everything you never wanted to know about basalts\nhttp://en.wikipedia.org/wiki/Basalts
784392
Here is what i found.  I'm not sure how right this is, but you can check it out.  Good Luck with your testing.
826018
It just so happens that I am working on developing a test method for explosives.  The results are as accurate as any other analytical method.  If you have samples that need to be tested you can try any environmental testing laboratory.  Send me a message at steve.rocks@yahoo.com
778322
this is too easy! just make sumthin up! you'll get a good grade! it doesnt have to be true!
200447
study............HARD!
695150
This past summer the wife and I took a trip to NC. Spruce Pine to be precise. We went "Rock Hounding" or "Gem Mining" at place called  Gem Mountain.\n\nhttp://www.gemmountain.com/aquamarine.htm\n\nWhile at Gem Mountain we purchased one bucket of minerals and mined at their Aquamarine mine near by.\n\nWe found some nice specimens, but one in particular stuck a nerve, The image of this Aquamarine is posted at my site, Take a look:\n\nhttp://my.opera.com/TheMineralExchange/albums/showpic.dml?album=157930&picture=2347315\n\nOk.. so after viewing the image, Aquamarine's stats are as follows:\nA) : Green-blue\nB) : White\nC) : 2.63-2.91\nD) : 7 1/2-8\nE) : Hexagonal\nF) : Imperfect\nG) : Conchoidal, Uneven, Brittle.\n\nHey Teacher?. did I pass?
161104
Check a Science Webquest website and you will find out...:D
699101
DO NT GET R QUESTION!
348133
Some rocks contain iron. When exposed to water it will oxidize & become iron oxide.\n\nSome sedimentary rocks are cemented together w/ rusty orange substance which is iron oxide.\n\nI know, I just handled some of it today in class. It got all over my hands.\n\n;)