Serpentine is California’s State Rock. It varies in color, from apple-green to black and has a shiny, wax-like appearance with a soapy or greasy texture.   It can be found throughout California’s mountain ranges, especially the Klamath Mountains, the coastal range, and the Sierra Nevadas.  Serpentine is a metamorphic rock . Serpentine rock is comprised mostly of Serpentinite, (Fe or Mg)3[Si2O5(OH)4].  It has a monoclinic crystalline structure.  Serpentine rock has a density of 2.5 and a harness between 4 and 6. Common types of serpentine rock are lizardite, chrysotile, and antigorite.  Antigorite is a green color with cloudy patches and grey-colored veins.  This form of Serpentine is often used in jewelry because it resembles jade. Chrysotile is very fibrous and is used commercially as asbestos.  These rocks contain only 1-5% asbestos; this amount of asbestos is not dangerous unless the rock is ground up.  Lizardite is a soft, translucent rock that is very fine-grained and is often marbled; it resembles mica.
            Serpentine is comprised of layers of sheet silicate tetrahedrons, with magnesium hydroxide layers between the sheets.  In Chrysotile, the layers bend into tubes, forming the fibers that are used as asbestos.  The other forms however, have mixed sheets that are not fibrous, and are thus not a cancer risk. These sheets make serpentine susceptible to cracking and it is easily discolored by weathering.

Rock Formation

Soil Composition

Serpentinite Flora

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Miscellaneous uses

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For more information, please visit:
http://faculty.washington.edu/toby/Serp.htm http://en.wikipedia.org/wiki/Serpentine
http://en.wikipedia.org/wiki/Image:Monoclinic.png
http://mineral.galleries.com/minerals/silicate/serpenti/serpenti.htm

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