Once mined in many places throughout the world but now mostly in Canada, Russia, Africa, and China, asbestos is a naturally-occurring mineral that was used for decades as an insulator for a host of products, many used in homes throughout the world.
Six different types of asbestos have been identified. These types are divided into two groups:
- Serpentine – This variety of asbestos has a layered structure and curly fibers. Chrysotile asbestos is the only type in this category and was the kind of asbestos most often used in buildings in the United States.
- Amphibole – This kind of asbestos is characterized by a long chain-like structure of fibers that are sharp and straight and easy to inhale. Found in this category are the remaining 5 types of asbestos – amosite, crocidolite, anthophyllite, tremolite, and actinolite. The first two were widely used in products until the 1980s and amosite is the 2nd most likely type to be found in buildings.
These kinds of asbestos are also often categorized by their color, though tremolite, anthophyllite, and actinolite remain unclassified.
- White – chrysotile
- Brown – amosite
- Blue – crocidolite