Staurolite – Now this is a cool mineral!

Staurolite Mineral Staurolite is a unique mineral which often forms cross-shaped twinned crystals. While staurolite is generally brown it has a colorless to grey streak and it is about as hard as quartz (7 to 7.5 on Mohs hardness scale). The name staurolite comes from the Greek word stauros which means “cross.” Staurolite forms in metamorphic rocks such as schists and gneisses.

Trivia:

Staurolite forms only in rocks which are metamorphosed within a narrow range of temperatures and pressures.
Because staurolite forms under specific conditions it is a good indicator mineral for determining the conditions under which a rocks forms.
Staurolite is found in Georgia, New Mexico, France and Brazil.