Chrysotile

Chrysotile

Chrysotile
 

Composition: Hydrous magnesium silicate (H4Mg3Si2O9 )

Physical Properties:
Color: Green to pale green to yellowish green, golden yellow to dark brown, gray
Streak: White
Luster: Silky to oily
Hardness: 2-3
Tenacity: Soft and flexible
Specific Gravity: 2.3-2.5
Cleavage: None

Crystallography:
System: Monoclinic
Twinning:
Habit: Crystals are bladed. Aggregates are massive and fibrous.

General Information:
Chrysotile is a mineral that separates into strong, flexible fibers. It is found as veins in serpentine rock, normally with the fibers oriented nearly perpendicular to the direction of the vein. These veins range in thickness from that of a pencil line to more than an inch, but most chrysotile veins are less than 1/8 inch thick. The color of chrysotile in the vein is green to greenish white, rarely golden, but when separated into a fluffy mass the fibers are white. Individual fibers are somewhat stronger than silk, and a bundle of fibers the diameter of a pencil lead cannot be broken by pulling between the fingers. Chrysotile is the principal asbestos mineral of industry. The term "asbestos" is a commercial one, applied to half a dozen fibrous minerals that are used primarily because of their fibrous characteristics. Of these, chrysotile is one of the strongest, and is also the most abundant; so it accounts for about 95 percent of the asbestos produced in the world. Serpentine containing chrysotile veins is mined at several localities in California for production of asbestos. The rock is crushed and passed over tilted shaking screens, allowing the small serpentine fragments and dust to fall through the screens and the fluffy fibers to be lifted from the end of the screens by air suction. Named in 1834 from the Greek words, chrysos, meaning gold, and tilos, meaning fiber.

California Counties in Which this Mineral is Found
 

Alameda
Amador
Calaveras
El Dorado
Fresno
Humboldt
Imperial
Inyo
Kern
Lake
Los Angeles
Monterey
Napa
Placer
Riverside
San Benito
San Bernardino
San Diego
San Francisco
Shasta
Siskiyou
Trinity
Tulare
Tuolumne
 

Information on Specimen Photo:
Specimen Description: Chrysotile veinlet, 1 cm wide, El Dorado County. California Division of Mines and Geology.
Photographer: Max Flanery, CGS