Definition of asbestos (types of)

1) Chrysotile, or white asbestos, is obtained from Canadian serpentine rocks. It is less friable (and therefore less likely to be inhaled) than the other types and is the type most often used industrially. Chrysotile should not be confused with chrysolite, a synonym of olivine.
Amosite, or brown asbestos, is an amphibole from Africa.Crocidolite, or blue asbestos, is an amphibole from Africa and Australia. It is the fibrous form of riebeckite.

Notes: Serpentine rocks are those with curled fibres. Amphiboles have straight, needle-like fibres.
The amphiboles, in their fibrous form, are friable and therefore the most carcinogenic, although they also exist in safer non-fibrous forms.
Other asbestos minerals, such as tremolite, actinolite and anthophyllite are not used industrially but occur in traces.