Tremolite

Tremolite, one of the amphibole group of minerals. It is composed of silica, magnesia, and lime, and has a hardness of 5·5 to 6, and a specific gravity of 2·9 to 3. It occurs usually in long prisms, white or gray, vitreous, and translucent to opaque, but frequently appears as fibrous asbestos-like aggregates with a silky lustre. Tremolite is usually associated with crystalline schistose rocks, often occurring in the granular limestones, and sometimes forming the chief material of the so-called tremolite-schists.