what is Andalusite? Where is it found?
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Andalusite is a polymorph with two other minerals; kyanite and sillimanite. A polymorph is a mineral that shares the same chemistry but a different crystal structure with another, or other, minerals. A unique variety of andalusite is called "chiastolite". It contains black or brown clay and/or carbonaceous material inclusioned in the crystal. These inclusions are arranged in regular symmetrical shapes. Usually they are in the form of a cross or X. \n\nPHYSICAL CHARACTERISTICS:\nColor is white, red, brown, orange and green. \nLuster is vitreous. \nTransparency crystals are transparent to translucent. \nCrystal System is Orthorhombic; 2/m2/m2/m \nCrystal Habits include prismatic crystals with a square cross section terminated by a pinacoid. also massive and granular. \nCleavage is good in two directions. \nFracture is splintery to subconchoidal. \nHardness is 7.5 \nSpecific Gravity is approximately 3.15+ (above average) \nStreak is white. \nAssociated Minerals are cordierite, biotite, feldspars, quartz, kyanite and sillimanite. \nOther Characteristics: dark inclusions produce cruciform shapes in the variety, chiastolite. Index of refraction is 1.632-1.638. \nNotable Occurrences include Andalusia, Spain; Austria; California, USA and China. \nBest Field Indicators are crystal habit, color, inclusions (if present) and hardness.
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Granite hornblende is a source of silicon.\nAs a start, have a look here:
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It's an iron oxide and it forms in an oxidising environment. Rich deposits may be the result of weathering, or precipitation out of oxygen-rich surface water or oxygen-rich water in hydrothermal veins.\n\nAs to why it is sometimes red and sometimes metallic-grey I'd say it is probably due to the size of the crystals. When it is ground up fine, it is always red. The smaller grains scatter red light.
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Too long to list:\nhttp://seis.natsci.csulb.edu/bperry/ROCKS.htm\ngood site
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Silver is an element.  It is found in rocks that are called ore.  It usually occurs as a sulfide mineral, such as AgS2, or in small amounts in a sulfide mineral based on another metal, such as PbS2.\n\nGold is Au.  Silver is Ag.
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I don't know but if you click on the site below you'll find out real quick. They know minerals.
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I found a very informative essay at the below address, which covers the removal of Alumina from Its Bauxite Ore.  The process is very complex because Alumina is not actually found in its raw state as part of the Bauxite compound.  Bauxite is heated and then through a process of chemical electrolysis alumina is extracted and forms aluminium.  More precise explanation can be found at below address.     \n\nhttp://www.patana.ac.th/parents/curriculum/Chemistry/units/LR803.html
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Crystal Gold is a color of granite, I don't know where it's from but Brazil is a good guess.\n\nIt looks like this\n\nhttp://www.montgranite.com/getMedia.php?targetObjectId=6086
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Hello,\n\n    The quotes below are taken from the Stillwater Mine web site. The deposit this mine uses in Montana is the largest palladium deposit in the world and unusual in that it contains much more palladium than platinum:\n\n"The platinum group metals (PGM) occur both in primary deposits and placers. The primary deposits are of two main types. The first consists of local concentrations of the metals in olivine-rich rocks, particularly in dunite. Often associated with chromite, native platinum or iridosmine is the principal constituent. The erosion of such deposits has been responsible for the formation of placer deposits of the platinum metals. The most important commercial dunite deposits are in the Ural Mountains of Russia and at the Overwacht in the Transvaal in South Africa. \n\nThe second type of primary deposit includes nickel-copper sulphide deposits that are generally associated with norite. These deposits, in which platinum and palladium predominate, make up the greatest known reserves of PGM metals. The most extensive deposits have been found in the norite belt of the Bushveld Igneous Complex in the Transvaal, the Stillwater Complex in Montana, USA, in the Sudbury district of Ontario Canada and the Norilsk Complex in Russia."\n\n    I hope that helps,\n\n    Steve
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Agate & Quartz are both composed of SiO2 or silicon dioxide.\n\nAgate is a cryptocrystalline version of quartz.(very small, as not to be seen with the naked eye, crystals) \n\nAgate is formed in sedimentary deposits from dissolved quartz that is redeposited. This is usually near the surface where there is lower pressure & temperatures.\n\nMany times agate is found as geodes. These are really cool. Sometimes they fill in completely w/ layers of silica. Other minerals may be present as to make color bands. Other times the geode will not fill completely in before crystals start forming. WOW! Love these!\n\nSometimes from the process mentioned above, cryptocrystalline silica will seep into bones & remnants of tree trunks. Ever seen petrified wood? OF course this is not the only mineral that will do this in wood & bones.\n\nOpals are also a variety of quartz. It contains minute amounts of water in its structure. The only difference here is that opals are amorphous meaning that there are no crystals.\n\nSilicon Dioxide is the most abundant mineral in the earth's crust. It is found everywhere and in all kinds of forms.\n\n:)
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Feldspar is the name of an important group of rock-forming minerals which make up perhaps as much as 60% of the Earth's crust. Feldspars crystallize from magma in both intrusive and extrusive rocks; they occur as compact minerals, as veins, and are also present in many types of metamorphic rock. Rock formed entirely of plagioclase feldspar (see below) is known as anorthosite. Feldspars are also found in many types of sedimentary rock.\n\nThis group of minerals consists of framework or tectosilicates:\n\n- orthoclase a potassium-aluminium silicate,\n- microcline also a potassium-aluminium silicate, and\n- plagioclase a sodium-aluminium silicate to a calcium-aluminium silicate isomorphous series:\n          o albite\n          o oligoclase\n          o andesine\n          o labradorite\n          o bytownite\n          o anorthite.
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Uranium is a naturally occurring element found at low levels in virtually all rock, soil, and water. It is considered to be more plentiful than antimony, beryllium, cadmium, gold, mercury, silver, or tungsten and is about as abundant as arsenic or molybdenum. It is found in many minerals including uraninite (most common uranium ore), autunite, uranophane, torbernite, and coffinite. Significant concentrations of uranium occur in some substances such as phosphate rock deposits, and minerals such as lignite, and monazite sands in uranium-rich ores (it is recovered commercially from these sources).\n\nThe decay of uranium, thorium and potassium-40 in the Earth's mantle is thought to be the main source of heat[5][6] that keeps the outer core liquid and drives mantle convection, which in turn drives plate tectonics.\n\nYou can find deposits of uranium by using a Geiger counter or by looking for other kinds of rock that uranium is found near.\n\nPlutonium, on the other hand, is not naturally occuring.  You can make plutonium by "enriching" uranium in special reactors.
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Iolite is a mineral sometimes used as a gemstone. Gem quality  a sapphire blue in color to a bluish violet color to yellow gray in color depending on refraction of light It is found in Burma and Sri Lanka. Actually called, cordierite. On the Mohs hardness scale about 7 to 7.5\n The two stones can be confused but are very different and especially when price comes into the conversation as tanzanite is a rare stone that is very very pricey.\nTanzanite is a marketing name by Tiffany & Co. and this stone is not popular with alot of people because of the mining industry of Tanzania. They make a great deal of money off this stone while using methods many people find deplorable. It is still. It is a  purple stone generallly after heat treating because it comes out of the ground a bronze color. It has a Mohs hardnes of 6.5 to 7
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Hematite is an iron ore that is use in jewelry and is often sold at rock shops for rock and mineral collectors.\n\nLook in your phone book for Rock Shop or Mineral Shop\nTry a Yahoo Local search for "rock shop" or "mineral shop" for your community.\nThere are some retailers online that will sell you hematite samples.  Try a Yahoo Search (below) and browse through the results.
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Tennantite is a copper arsenic sulfosalt mineral. Its chemical formula is Cu12As4S13. It is found in hydrothermal veins and contact metamorphic deposits. A closely related mineral, tetrahedrite (Cu12Sb4S13) has antimony substituting for arsenic and the two form a solid solution series. The two have very similar properties and is often difficult to distinguish between tennantite and tetrahedrite. Iron, zinc, and silver substitute up to about 15% for the copper site.\n\nThe mineral was named after the English chemist Smithson Tennant (1761-1815).\n\nhttp://en.wikipedia.org/wiki/Tetrahedrite
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Iridium is a mineral found along the K/T boundary.  Some scientists speculate that iridium is not a native mineral to Earth and is only found here in a thin layer along the surface because of the huge meteor impact that apparently killed off the dinosaurs.
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It sounds like a mineral called chrysotile. This is a fibrous mineral, sometimes green, that is a type of asbestos. Link to a picture is here:http://geology.about.com/library/bl/images/blchrysotile.htm\n\nIf you have more properties to describe it with you may find more information using this mineral search engine:\nhttp://www.mindat.org/fullsearch.php