Tremolite

Physical Properties
Chemical formula Ca2Mg5Si8O22(OH)2
Class Inosilicate
Single chains of linked tetrahedra
Crystal system Monoclinic
Habit Prismatic
Radiating or parallel blades
Asbestiform
Columnar
Color White, green
Hardness 5 to 6
Specific gravity 3.0 to 3.3
Cleavage Two perfect prismatic {110}
Fracture Uneven
Luster Vitreous
Silky
Transparency Transparent to translucent
Streak White
Optical Properties
PPL Colorless
Green and weakly pleochroic if Fe is present
“60/120” cleavage (56° and 124°)
XPL Upper 1st order to 2nd order colors
δ 0.022
after Perkins, 331-332

Tremolite in Hand Sample

Tremolite

Acicular tremolite in quartzite

Scanning electron micrograph of tremolite

Tremolite in Thin Section

Thin Section GigaPans

Tremolite in talc-tremolite schist, plane polars

Tremolite in talc-tremolite schist, crossed polars

Tremolite, PPL
Tremolite, XPL

Further Reading

Tremolite at webmineral.com

Tremolite at mindat.org