|Prasiolite: "Green Amethyst"??|
Why do people sell, and buy, something called "green amethyst"? What is it? Where does it come from? Does it have anything to do with amethyst?
What people are selling and buying is actually something known by gemologists as prasiolite. The name comes from the Greek word for "leek-green." Prasiolite is a golden green quartz, somewhat similar in color to peridot, or lemon quartz!
Here's the most interesting thing: there is no such thing as "natural" or "untreated" prasiolite! Prasiolite (or green quartz) starts as amethyst, or pale yellow quartz, and is heated until the green color is achieved. However, not all amethyst or yellow quartz can be heated to produce prasiolite. According to gemological sources, only quartz from the Montezuma deposit in Minas Gerais, Brazil can be heated to produce prasiolite. The quartz is heated to about 500 degrees centigrade to produce the light golden-green color.
Unfortunately, the color is not stable and is known to fade when exposed to strong sunlight!
|Synthetic Green Quartz|
Are there any naturally-occurring green quartz stones?
Yes. There are members of the chalcedony family that are natural, translucent green stones: chrysoprase and aventurine. Chrysoprase is a natural stone that varies in color from apple green to deep green. Aventurine is a natural green stone with glittery mica inside!
So then why is Prasiolite sold as "Green Amethyst"?
Sadly, the answer is perhaps greed, or what I like to call, "creative marketing".
Since amethyst is the most valuable gem in the quartz family, calling this green heated quartz "amethyst" is just an attempt to "elevate" prasiolite and charge a premium for the stone. I guess that, if it's genuine prasiolite, it began as amethyst and then is heated to achieve the green color, it's not a complete fabrication, but it is a stretch!