Description
Lizardite is related to serpentine and resembles it very closely. The mineral serpentine, or clinochrysotile, is a magnesium-iron silicate with the chemical formula (Mg, Fe)3Si2O5(OH)4. It belongs to the phyllosilicate family. This amorphous mineral can be red, yellow, white, and green. The green color is typical of the mineral in the mantle rock serpentinite. Its hardness is 2.5 to 4, depending on its composition, and serpentine has an average density of 2.59. One of these species is classified as 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 within the rock is reminiscent of a snake. It was also used in the past as a remedy for snakebites. The other name for serpentinite, clinochrysotile, is derived from the Greek words clinos, chrysos, and tilos ("crooked," "gold," and "fiber," respectively). It is so named because of the gold-colored, fibrous structure the mineral can assume. 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 sometimes called serpentinitization. The chemical reaction equation is: 4Mg2SiO4 (olivine) + 4H2O(l) + 2CO2(aq) → Mg6Si4O10(OH)8 (serpentine) + 2MgCO3 (magnesite) Serpentine is therefore a mineral found in areas where mantle rock has reached the surface, usually in orogens. Serpentine is widely exposed in Greece and the Alps.
