While prasiolite can occur naturally, most of it is created by heat treating lighter shades of purple amethyst, which is also quartz, until it lightens to a pale green. The resulting stone is ...

Amethyst may develop into the more common citrine and rarer green quartz naturally under certain geologic conditions. On the California-Nevada border, just north of Reno, amethyst, citrine, and green ...

The finest amethyst color is a strong reddish purple or purple with no visible color zoning. Dealers prefer strongly saturated reddish purple to dark purple, as long as the stone is not so dark that ...

Amethyst, on the other hand, appears purple because it absorbs light in the yellow and green regions, reflecting a mix of blue and red. This interaction between light and the gemstone’s atomic ...

Amethyst is your stone. Its purple hue represents calmness and clarity ... Guide for tips and information on how to find the right diamond for you. Time to go green—May’s gem is emerald. Known for its ...