Asbestos General Information Asbestos is a term used for several types of naturally-occurring fibrous minerals found in many parts of California. The most common type of asbestos is chrysotile, but other types are also found in California. Serpentine rock often contains chrysotile asbestos, especially near fault zones. Serpentine rock is abundant in the Sierra foothills, the Klamath Mountains, and Coast Ranges.
Asbestos is released from serpentine rock when it is broken or crushed.
This can happen when cars drive over unpaved roads or driveways which are surfaced with serpentine rock, when land is graded for building purposes, or at quarrying operations. It is also released naturally through weathering and erosion. Once released from the rock, asbestos can become airborne and may stay in the air for long periods of time. Other sources of asbestos are in man-made products. The most common sources are heat-resistant insulators, cement, furnace or pipe coverings, inert filler material, fireproof gloves and clothing, and brake linings.