緑の水晶 from China

こんなページがありました。
http://www.the-vug.com/vug/vugfakes.html

Green quartz can be produced in the lab by a modification of the process used to manufacture large, high-quality quartz crystals for electronics applications. The process involves heating the quartz with water under high pressure. This causes the quartz to recrystallize. If other substances are present these might be included into the new crystals. For example inclusion of chromium can result in deep green quartz. So, existing quartz clusters (often with damaged crystals tips because these clusters are essentially worthless) are heated with water under high pressure, producing clusters with new deep green tips. These tips have a characteristic etched or stepped growth pattern. The material is lab-grown and not produced in any mine, despite what some dealers might want you to believe.

ふむふむ。クロムか。黄色のオーケン石もありますね。