Archives for March, 2013

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Emerald Chemical Formula

Beryl on calcite(credit: Rob Lavinsky, cc-by-sa-3.0) The chemical formula for emerald is Be3Al2(SiO3)6. Note that the formula for emerald is actually that of beryl. This is because emeralds are a variety of beryl. The green color in emeralds is due to trace impurities (usually due to chromium, but also sometimes vanadium.) Pure beryl is colorless, but due ...
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Diamond Chemical Formula

The chemical formula for diamond is C. This is because diamonds are pure carbon. In fact, they're an allotrope of carbon. The crystal structure of diamond is a diamond lattice. This lattice help prevent impurities. This, in turn, causes many diamonds to be colorless. I love the inclusions on this one!Image credit: Steve Jurvetson
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What is the chemical formula for quartz?

The chemical formula for quartz, Earth's second-most abundant mineral, is SiO2 (silicon dioxide.) Did you know amethyst and citrine are actually varieties of quartz? Impurities such as iron (found in both amethyst and citrine) cause quartz to vary in color. Varieties of quartz (top right, pure quartz)Image credit: Mauro Cateb
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