Asbestos is a set of six naturally occurring silicate minerals, which all have in common, their asbestiform habit: i.e., long (roughly 1:20 aspect ratio), thin fibrous crystals, with each visible fiber composed of millions of microscopic "fibrils" that can be released by abrasion and other processes.
A 2635 (OTTO) Asbestos powder, for gooch crucibles Cas 1332-21-4 - used in automobile brake pads, shoes, and clutch discs, contaminants of amphiboles were present.