what is the pressure of  crystal silimanite and what is the pressure of  fibrous silimanite(fibrolite).?
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Crystal Silimanite\n \nMolecular Weight (g/mol.) 162.04558 \nApparent Density (g/cm3) 3.24 \nBulk Density (g/cm3) 3.24 \nMelting Point (°F) 3290 \nBoiling Point (°C)   \nSurface Area (m2/g)   \nThermal Conductivity (cal/s-cm-°C)   \nMohs Hardness @20°C 6 - 7 \nSpecific Gravity (g/cc) 3.2 \nParticle Shape   \nScreen Analysis   \nCrystallography orthorhombic \n\n\n\nFrom what i am reading they are the same
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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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Here's the pages with the info. You'll have to read fast. Don't wait so long next time. Good Luck!!\n\nhttp://mineral.galleries.com/minerals/gemstone/aquamari/aquamari.htm\n\nhttp://mineral.galleries.com/minerals/silicate/garnets.htm\n\nhttp://mineral.galleries.com/minerals/gemstone/class.htm
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Here are some potential sources:\n\nhttp://www.bestcrystals.com/ulexite.htm\n\nhttp://www.northwestnatureshop.com/department/Rocks_and_Minerals/Rock_and_Mineral_Specimens/592.html\n\nI'm sure you could find more if you googled it like I did.
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mafic magma - about 1100 Celcius\nintermediate magma - about 1000 Celcius\nfelsic magma - about 800 Celcius
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The 'science guru' is right, but I'll chime in to try and help you wrap your mind around it. \nThe slower magma cools the bigger the crystals in it get. The deeper the magma is in the earth the more it is insulated (like a pizza in one of those pizza delivery bags) and so it cools lots slower the deeper it is.\nThe faster the magma cools the smaller the crystals in it. Since the earth insulates the magma it has to get closer to the surface before it can cool fast enough to have small crystals.\nIf you have two different sizes of crystals then you must have two different rates of cooling.\nThe crystals that can form at higher temps start forming first, of course, and then, when the magma gets pushed up nearer the surface the rest of the material cools quickly into small crystals that surround the larger ones.\nDoes that help?
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Here is a chart of various estimates of the mantle's composition that have been made:\nhttp://www.mpch-mainz.mpg.de/~jesnow/Ozeanboden/2004/Lecture4/Composition.html\n\nThe answer in terms of minerals is (I quote) "The uppermost mantle is comprised of a peridotite with about 60% olivine 30% enstatite 6% clinopyroxene, 2% plagioclase and 2% spinel. At slightly greater depth, the plagioclase disappears and is replaced by spinel and clinopyroxene. Deeper still, garnet appears." from the above site. \n\nThe other thing you should realize is that while the earth's mantle may be 'plastic' it is not molten. From Wikipedia: "Although these temperatures far exceed the melting points of the mantle rocks at the surface, particularly in deeper ranges, they are almost exclusively solid. The enormous lithostatic pressure exerted on the mantle prevents them from melting."  From: http://en.wikipedia.org/wiki/Mantle_%28geology%29\n\nMagma coming from volcanoes actually originates in the asthenosphere, which is above the mantle.
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Unexpanded or raw perlite has a specific gravity of around 1.1 g/cm^3, or slightly more dense than water.\n\nPerlite is unusual in that it contains a lot of water in its composition, and when heated it expands like puffed wheat.\n\nWhen it is expanded, perlite has a density of 0.03 to 0.15 g/cm^3, or considerably less dense than water.  Expanded, it makes a pretty good thermal insulator.  \n\nIn horticulture it fills soil area and makes it more open to air, while still retaining considerable water.  In this application it is also known as vermiculite.\n\nFor more info about perlite, check out this website: http://www.perlite.info/indexes/main.html
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Ferromagnesium minerals: silicates with iron and magnesium in their formula, dark colored and dense. Example includes hornblende. \nNonferromagnesium mineral: silicates with no iron or magnesium in their formula (calcium, sodium or potassium common), light colored. Example includes feldspar.
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Stable in what regard?\n\nIf you want to know the compound which cannot be out-oxidated, it would be CsF, Cesium Fluoride. Dissolves in water fairly easily, so it isn't a stable crystal.
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They have a chemical structure which causes it to stay thick (viscous). The first crystals to form as a silicic magma cools slowly are pyroxene, amphibole, and feldspar. In pyroxene, silica tetrahedra (SiO4) form long chains. In amphiboles, silica tetrahedra form double chains. The pyroxene and amphibole crystals that are beginning to form become entangled so the magma becomes viscous.
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WHICH metamorphic rocks?  It will vary depending on the "ingredient" rocks and HOW they are metamorphing (pressure, heat, both pressure and heat)
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Probably silicone and iron.   It's a friggin big rock.   Hollow it out a bit; near the center the gravity is probably near earths gravity.
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If we put two smooth glasses together (without glue them), normally what is the distance in between? \nIn an ideal situation, let's say the two glass surfaces are perfectly smooth and 100% flat, and we superpose one of them onto the other, there should be an uniform distributed air-layer between the two pieces of glasses even though it looks we put them in direct contact, so what is the thickness of this air strip? round 10nm? or more than 1 μm?\nAny guess is welcomed :)\n\n\nif ur mentioning that it is an ideal situation - glass 100% smooth etc. then it is stupid of u to ask such a question. \n\nThere wud b no air gap b/w them.\n\n(ur quest included so u may not modify it later)\n\n\nArchitectural glass is made from three principal raw materials, easily found in nature: silica, lime and sodium carbonate.\nAvg size of molecular terrain would be approximately 300 - 3000A. (neglecting secondary composition of glass). Thus logically this has to be the thickness of this strip of air.
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what are the properties of minerals?\n...\nsorry thats all i got
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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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Schist = cooked mud (i.e. no water left trapped, clay minerals got cooked to less water containing minerals such as micas). How long depends on the thickness of the sedimentary rocks deposited on top of the particular clay layer (pressure helps evacuate water and increases temperature); whether or not there is an external heat source (volcanic activity, magma chamber nearby, metamorphic processes - faults, etc.). SO - time can't be specified unless is a case study, temperature -  between 150 and 200 degrees C. Above 200 c is the schist kingdom in metamorphic rocks.