what are isotropic and anisotropic  minerals?
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Distinguishing between the two mineral groups with the microscope can be accomplished quickly by crossing the polars, with the following being obvious:\n\nAll isotropic minerals will appear dark, and stay dark on rotation of the stage. \nAnisotropic minerals will allow some light to pass, and thus will be generally light, unless in specific orientations. \nWhy are isotropic materials dark?\n\nIsotropic minerals do no affect the polarization direction of the light which has passed through lower polarizer; \nLight which passes through the mineral is absorbed by the upper polar. \nWhy do anisotropic minerals not appear dark and stay dark as the stage is rotated?\n\nAnisotropic minerals do affect the polarization of light passing through them, so some component of the light is able to pass through the upper polar. \nAnisotropic minerals will appear dark or extinct every 90° of rotation of the microscope stage. \nAny grains which are extinct will become light again, under crossed polars as the stage is rotated slightly\n\nAnisotropic minerals differ from isotropic minerals because:\n\nthe velocity of light varies depending on direction through the mineral; \nthey show double refraction. \nWhen light enters an anisotropic mineral it is split into two rays of different velocity which vibrate at right angles to each other.\n\nIn anisotropic minerals there are one or two directions, through the mineral, along which light behaves as though the mineral were isotropic. This direction or these directions are referred to as the optic axis.\n\nHexagonal and tetragonal minerals have one optic axis and are optically UNIAXIAL.\n\nOrthorhombic, monoclinic and triclinic minerals have two optic axes and are optically BIAXIAL\nbasically the ones light can travel thruogh are isotropic, like garnets,emeralds,quartz.\nminerals light does not travel through are anisotropic.
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ulexite, ullmannite, ulvospinel\nxenotime\nzahatite\nzappinite
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Geology is an earth science and is the study of rocks and minerals.
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phyllite, basalt, slate, shale. There are many types of schist. It is defined mainly as being a plated metamorphic rock in which the mineral crystals can bee seen with the naked eye.
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Mineral Maps of Australia\nhttp://www.ga.gov.au/map/
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Bowen's reaction series is what you're looking for.\n\nIn a nutshell, the rate of cooling, temperature, and magma composition determine which minerals form and the ultimate rock type.  The links provide more information.
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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
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* rock - mineral matter of variable composition, consolidated or unconsolidated, assembled in masses or considerable quantities in nature, as by the action of heat or water. \n* Igneous rock - rock formed by the solidification of molten magma\n* metamorphic rock - rock altered by pressure and heat\n* sedimentary rock - rock formed from consolidated clay sediments
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the basic building blocks of all rocks, minerals, liquids, and gases are chemical elements, which are made up of various combinations of atoms. For example, when lead atoms combine with sulfur atoms, the mineral galena is formed.\n\nA mineral is a naturally occurring solid with a definite chemical composition and crystal structure. Rocks are naturally occurring solids composed of one or more minerals. Rocks are identified by the minerals they contain and are grouped according to their origin into three major classes: sedimentary, igneous, and metamorphic. Each group is subdivided on the basis of texture and mineral composition\n\ndoes this help?\n\nsupposedly you can.
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Alfisols, Aridisols, Entisols, Histosols, Inceptisols, Mollisols, Oxisols, Spodosols, Ultisols, Gelisols, Andisols, and Vertisols. \n\ngo here little one\nhttp://soils.ag.uidaho.edu/soilorders/orders.htm\n\nand here\nhttp://www.enchantedlearning.com/geology/soil/
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Agate is a type of the mineral family chalcedony --\nJasper is a type of the mineral family quartz --\n\nSee this website for pictures -->http://www.mindat.org/min-2082.html\n\nGod is spelled B-I-G  B-A-N-G\n\nPBrax@netscape.com
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Well, it won't be easy.  The two differ only in one way: Spessatite has Mn, while Hessonite (which is a subtype of grossular) has Ca.  The colours are also similar: Spessatite is ususally deep red but may also be black to orange, dark pink, or brown.  Grossular/Hessonite is more likely to be nearly colourless to green, yellow, pink, or brown.\n\nThe best way to tell them apart may be by the assemblage in which they occur.  Hessonite tends to be more commonly associated with skarns and other metamorphosed carbonate-bearing rocks, and is usually associated with calcite, dolomite, wollastonite, tremolite, and epidote.  Spessatite on the other hand tends to more commonly occur in granites, pegmatites, and other felsic igneous rocks, and in Mn-rich metamorphic rocks.\n\nThe only sure way to tell though would be to put them on a microprobe to find out.\n\nGood luck!
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Rock is a naturally occurring aggregate of minerals and/or mineraloids. Rocks are classified by mineral and chemical composition; the texture of the constituent particles; and also by the processes that formed them. These indicators separate rocks into igneous, sedimentary, and metamorphic.\n\nMinerals are natural compounds formed through geological processes. The term "mineral" encompasses not only the material's chemical composition, but also the mineral's structure. Minerals range in composition from pure elements and simple salts to very complex silicates with thousands of known forms (organic compounds are usually excluded)
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Here, try this:\n\nhttp://www.rocks-and-minerals.com/\n\nCheers.
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Shales can be changed into schist by way of moderate heat or shearing pressure accompanying regional (tectonic) deformation\n\nIf you are asking for specific minerals, it can be quartz, micas, amphiboles; often garnets, kyanite, or other aluminosilicates
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If you are looking for a general model, this link should help.  The United States Geological Survey (USGS) always a good soure for geology and earth science related questions.
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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.