Tremolite

History: Named in 1789 by Johann Georg Albrecht Höpfner for the Tremola Valley (Val Tremola), Central St Gotthard Massif, Tessin, Switzerland. 

Tests: Insoluble in acids. 

Uses: Used for fire retardant materials.  May be highly fibrous and included as an asbestiform mineral; considered carcinogenic if ground and inhaled.  Use care in handling.

Properties

Cleavage Perfect
Color Colorless, white, gray, pink, green, brown
Crystal Systems Monoclinic
Fracture Uneven
Hardness 5-6
Specific Gravity 2.9-3.2

Group

Silicates

Composition

Ca2Mg5Si8O22(OH)2