Serpentine hand-cut Spheres from Pakistan.

The mineral serpentine or clinochrysotile is a magnesium iron silicate with the chemical formula (Mg, Fe)3Si2O5(OH)4. It belongs to the phyllosilicates. The amorphous mineral can be red, yellow, white and green. The green color is typical of the mineral in the mantle rock serpentinite. The hardness is 2.5 to 4 depending on the composition and serpentine has an average density of 2.59. One of these types falls under asbestos. Inhalation of this species is harmful to health. The mineral serpentine, like the rock serpentinite, is named after the Latin word serpens, meaning "snake". The shape in which the minerals have grown in the rock is reminiscent of the shape of a snake. It was also used as a medicine against snakebites. The other name for serpentinite, clinochrysotile, is derived from the Greek words clinos, chrysos, and tilos ("crooked, crooked," "gold," and "fiber," respectively). It is so named because of the gold-colored fibrous structure that the mineral can adopt. Serpentine is an indicative mineral for serpentinite, a peridotite often converted by hydrothermal activity. Under the influence of pressure and temperature, the olivine and pyroxene from the mantle rock are converted into serpentine. This is known as serpentinitization. The chemical equation is: 4Mg2SiO4 (olivine) + 4H2O (l) + 2CO2 (aq) → Mg6Si4O10(OH)8 (serpentine) + 2MgCO3 (magnesite) Serpentine is therefore a mineral that is found in those areas where mantle rock meets the surfaced, usually in orogens. Serpentine is widely exposed in Greece and in the Alps.