Tuesday, June 19, 2007

Blue Quartz From Minas Gerais, Brazil

The amethyst mine of Montezuma in the northern part of the Brazilian state of Minas Gerais produces amethyst which can be modified to green by heat treatment. In the trade the treated gems are sold as prasiolite. If the stones are exposed to gamma ray treatment, the stones may turn blue.

No comments:

Post a Comment