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I need help with my gemology assignment question: What is the chemical formula for a synthetic ruby?

+1 vote
asked Mar 13, 2016 by Ruby (130 points)

1 Answer

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Aluminum oxide is a mineral known as corundum, the red which makes it ruby comes from a small percentage of the aluminum ions being replaced by chromium. Synthetic rubies have the same formula. All natural rubies have inclusions and what is known as "silk" also called rutile needles. These things are how natural rubies are distinguished from synthetic ones.

answered Mar 16, 2016 by Weasel (58,360 points)