Serpentine

The serpentine subgroup (part of the kaolinite-serpentine group) are greenish, brownish, or spotted minerals commonly found in serpentinite rocks. They are used as a source of magnesium and asbestos, and as a decorative stone. The name is thought to come from the greenish color being that of a serpent.
The serpentine subgroup are a set of common rock-forming hydrous magnesium iron phyllosilicate () minerals, resulting from the metamorphism of the minerals that are contained in ultramafic rocks. They may... more