Epidote · Zoisite

Tanzanite

Tanzanite is the heat-treated blue-violet vanadium zoisite of Tanzania's Merelani Hills — a one-source, strongly trichroic December birthstone.

Colour
blue

Transparency
Transparent

RI
1.691–1.700

SG
3.10–3.45

Mohs
6.0–7.0

Birthstone
December

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