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what causes the color purple in the mineral SiO2

–1 vote
asked Feb 8, 2018 by brittney (110 points)

2 Answers

0 votes

Purple SiO2 is Amethyst. It is caused by several things, irradiation by heat or light and iron impurities which sometimes combine with trace elements. I have seen it in the amethyst mines, red, black, brown, white, clear and different shades of purple. I've seen pieces as big as a car. Google the largest amethyst mine in the world. It is up in Ontario not far from Kakabeka falls. That is the second biggest waterfall east of the Mississippi on the North American continent. The flies are terrible but it was still fun.

answered Feb 9, 2018 by Weasel (58,800 points)
0 votes
it is amethist as i know
answered Feb 14, 2018 by vickidcasey (270 points)