Serpentine

Serpentine is a gem-quality hydrated magnesium silicate, usually green, yellowish-green, or brownish-green in color. Its name thought to derived from its serpent-like green colors. It is not just a gemstone, but rather, it is a group of minerals which includes up to 20 different related members. Although there are a variety of serpentines, there are only two basic aggregate structures of serpentine which include antigorite and chrysotile.

Serpentine is a basic magnesium silicate, with many specimens containing iron as well. Other elements in small quantities may also be present, including chromium, nickel and cobalt. Most rocks are translucent to opaque. Hardness score can range from 2.5 to 5.5, depending on exact composition.

Serpentine is fairly soft and light. Specific gravity (density) ranging from 2.44 to 2.62, which is slightly lower than quartz. Its luster can be greasy, waxy or silky. It can sometimes confused with nephrite jade, but nephrite is much harder, tougher and has a less greasy luster.