Talc - Brigham Young University–Idaho

usually not green color. usually glassy Crystal Quartz (amathyst) Chalcedony . waxy (candle wax) Plagioclase. NaAlSi3O8 to CaAl2Si2O8. one of two feldspars (60% of minerals on Earth’s surface) striations. harder than steel. good cleavage. white to gray. Orthoclase (K-feldspar) KAlSi3O8. one of two feldspars. harder than steel. good cleavage ................
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