Other Related Areas

Serpentine and Amphiboles are the two main forms of asbestos. Serpentine asbestos is made of curly and flexible fibers. Amphibole asbestos is made of thin rod or needle like fibers. Due to its flexibility, serpentine is the more commonly used type of asbestos.

Chrysotile is the only type of asbestos that falls into the serpentine category, and is the most widely used type of asbestos. Chrysotile is commonly used in the raw and in manufactured products such as asbestos cement, roof and siding shingles, brake linings, pipe insulation, joint compound and floor tiles. It can also be spun and woven into fabric, and used to make asbestos rope, fire aprons and other materials. The majority of chrysotile asbestos is mined in and imported from Canada.Amphiboles are the less common type of asbestos, but have been used for industrial purposes throughout the world. The following are the five regulated types of amphibole asbestos:

  • Amosite, commonly referred to as “brown asbestos,” is an amphibole originating in S. Africa. This type of asbestos is most frequently used as a fire retardant in insulation products as well as in ceiling tiles.
  • Crocidolite Asbestos also referred to as the “blue asbestos” is an amphibole that is commonly found and mined in parts of Africa and Australia. Amosite and crocidolite are the most common types of amphibole asbestos.
  • Tremolite Asbestos is an amphibole that has been found in the United States. It is most commonly associated with W.R. Grace’s “Zonolite” insulation. “Zonolite” is comprised mainly of vermiculite, which mineral is commonly found in the earth alongside asbestos. Until 1990, over 80% of vermiculite mined in the United Sates came from W.R. Grace’s mine in Libby, Montana, which was contaminated with Tremolite asbestos. 
  • Anthophyllite Asbestos is one of the more rare forms of amphibole asbestos. It was not widely used in manufacturing, but it was commonly used in caulks.
  • Actinolite Asbestos is one of the lesser used forms of amphibole asbestos. It is bright green in color, and the nephrite variety of actinolite is one of the two minerals called Jade. Actinolite was not widely used in manufactured products, but may be found in some types of insulation.