The purple variety of quartz.   The location where Amethyst is found can influence colour – African amethyst tends to be quite dark in high grades and Brazilian amethyst tends to a medium purple hue.   “Rose de France Amethyst” is a pale lilac with a pink tint and is also called “pink amethyst”.  When purple amethyst is heated it can turn green – this can happen naturally or can be treated by heat.  This light sage green amethyst is called “greened amethyst”, “green amethyst” or “prasiolite”.  “Cape amethyst” is a variety with purple and white banding.