Description
STAUROLITE CRYSTALS
This is the brown staurolite crystals with garnet in mica schist. Dimensions: 4.1 x 2.6 x 1.3″ (10.5 x 6.5 x 3.3cm). Weight – 7.7oz (217 grams). Origin: Russia, Siberia.
Some information about staurolite:
Staurolite is a reddish brown to black, mostly opaque, nesosilicate mineral with a white streak. It crystallizes in the monoclinic crystal system, has a Mohs hardness of 7 to 7.5. Magnesium, zinc and manganese substitute in the iron site and trivalent iron can substitute for aluminium.
Staurolite often occurs twinned in a characteristic cross-shape, called cruciform penetration twinning.
The name derived from the Greek, stauros for cross and lithos for stone in reference to the common twinning.
