Asbestos Information Page

Sources, problems, health impact, using at work, identification and disposal of asbestos

What is asbestos?

Asbestos (derived from the Greek word for inextinguishable) is a term used for the fibrous form of a number of naturally occurring silicate minerals (part of the amphibole double-chain silicates and serpentine sheet-silicate mineral groups). Asbestos has been mined for many years in countries such as Canada, the United States, Australia, South Africa and Russia. The three main types of commercially used asbestos are:

Other asbestos types, such as the fibrous amphiboles Anthophyllite, Tremolite and Actinolite, are in use. However these are of a lesser commercial significance than the three types highlighted above. The asbestos colours cannot be seen with the naked eye. Asbestos materials generally look grey, white or a mixture with dark patches. There is no simple test to identify the asbestos type. Consequently the asbestos type can only be identified with certainty by appropriate laboratory analysis.

  • Amosite ('brown asbestos') named after Asbestos Mines of South Africa, it is a fibrous variety of Grunerite an iron-rich variety of the magnesium-iron Cummingtonite-Grunerite series of amphiboles.

Chemical formula: (Fe,Mg)7Si8O22(OH)2.

  • Chrysotile ('white asbestos'), a fibrous variety of magnesium silicate in the Serpentine group of sheet silicate minerals.

Chemical formula: Mg6Si4O10(OH)8.

  • Crocidolite ('blue asbestos') is a fibrous variety of the sodium-rich amphibole riebeckite

Chemical formula: Na2(Fe,Mg)5Si8O22(OH)2.

Last Updated: 25 March 2021