Asbestos is a naturally occurring group of fibrous minerals. It is thought that hot, mineral-bearing water flowed through cracks in rocks, and over time solidified, forming asbestos.
There are two main groups of asbestos – Amphibole (brown and blue asbestos) and Serpentine (white asbestos).
Asbestos is mainly found in Russia, Africa and Canada.
Smaller deposits can be found all over the world.