bentonite or montmorillonite?
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Montmorillonite's water content is variable and it increases greatly in volume when it absorbs water. Chemically it is hydrated sodium calcium aluminium magnesium silicate hydroxide (Na,Ca)x(Al,Mg)2(Si4O10)(OH)2·nH2O. Potassium, iron, and other cations are common substitutes, the exact ratio of cations varies with source.\n\nI would assume it could be magnetic, but not always. As for the affect/reaction I didnt find any information either way.
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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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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.
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One of inorganic.\n4 of Organic (Harder) Less if you take Microbiology.
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hope this helps you out. molding clay is what i would use.
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Question 1:\n\nPegmatites are rocks containing valuable mineral deposits such as quartz, feldspar, & mica. Gemstones are often associated w/ pegmatite deposits.\n\nQuartz is an important mineral in making glass & semiconductors/microchips as well as gemstones.\n\nFeldspar is used industrially in the glass-making process, in ceramics, & as gemstones (moonstone, etc.).\n\nMica is used in everything from paints to makeup. Anything w/ a sparkle. In the old days before glass became affordable, people used sheets of mica as windows on homes & in the doors of furnaces.\n\nThe link below gives a little insight into pegmatites & some history of mining in the United States.\n\nQuestion 2:\n\nHigher water content lowers the viscosity of magma (makes it less thick). This is b/c it disrupts the bonds between silicon & oxygen in the magma.
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pedilite, that is what my doctor said to give to my kids, i would check with your doctor first BEFORE doin anything
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I'd say acid. A base will corrode the skin, but an acid will burn. Trust me, it hurts.
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Both of these will reduce the size of the ore, and both are used.  I think that they use crushing first.
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sodium chloride or salt
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Silica weakly bonds to iteself (i.e. Hydrogen bonding) and it raises the viscosity.\n\nSo, low silica = runny lava, hi silica = thick lava
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It depends on what you're willing to pay and the effort you want to put into it.\nI'd always go rubber as it is stronger and more durable.\nLatex would be preferable to PVC.  I just don't think PVC cuts it on skin type things.
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Quartz & Feldspar make up most of the abiogenic sands (eroded from rocks).\n\nActually silica (silicon dioxide) & quartz are the same thing.\n\nThe other is feldspar which usually breaks down into clay depending upon the right surface conditions (wet/humid).
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Graphite and clay. The ratio of clay to graphite allows control of the hardness of the lead - more clay makes a harder lead.
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aluminium because its an alkali earh metal and\nfluorine is a halogen
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Silicon Dioxide\nSiO2
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Generally sandstones and quartzites are more weathering resistant. They tend to form mountains and ridges. Limestones and shales tend to weather more and form valleys. They can't hold a mountain up. \n\nDifferential weathering is where different formations or even bedding within the same formation, weather at different rates. Softer, less competent rocks weather faster than harder, more substantial rocks. Look at a road cut, some rocks stick out like massive sandstones, and underlying shales have weathered back into the hillside. The rocks have experienced the same weathering forces, but the shales have weathered faster. Look at a cross-bedded sandstone. Some bedding is prominent and sticks out, some has eroded back in the formation. Both are differential weathering.\n\nIn the big picture, the rocks on a mountain have resisted weathering, where the rocks in the valley floor have succumbed, Differential weathering.\n\nThe last part of your question; think of a cemetery. Which gravestones last the longest? Lots of pink granite ones, huh? Granite is a very hard metamorphic rock. It is the most resistant to weathering. Marble is metamorphosed limestone. Much harder than limestone, but still CaCO3 (Calcium Carbonate). Rain is slightly acidic, so marble will weather out, but very slowly. Sandstone is a sedimentary rock, softer than granite or marble. So there is your answer.\n\nI hope this helps.