Serpentine

Serpentine is not one mineral but the name for a subgroup of natural magnesium silicate minerals, mainly antigorite, lizardite and chrysotile, which usually occur mixed together as massive rock. The name comes from the snake-like markings of serpentine rock. It is soft, usually green, and is cut into beads, cabochons and carvings. Translucent varieties such as bowenite are often used to imitate jade, but serpentine is not jade.