Epidote is the name given to a group of complex silicates, but also denotes the most common individual member within this group. The mineral is almost always greenish in color, but ranges from a fairly light yellowish green to a dark green that verges on black. However, of most interest to collectors is the medium-toned pistachio green material, which is sometimes known as pistacite.

Epidote was named in 1801 from the Greek meaning “increase”, as one side of the prismatic crystals is longer than the other. These crystals tend to be well-formed and can be found in some interesting groupings, thus making them popular with mineral collectors. As a result, very few transparent epidote crystals are sacrificed for faceting.

Unakite is a green and pink rock that contains a mixture of epidote, orthoclase feldspar and quartz. It is usually tumbled, fashioned into cabochons or used for carvings.