JDMISGem Reference
Vesuvianite group · Idocrase (Vesuvianite)

Grey-Black Idocrase

Grey-Black Idocrase — Idocrase (Vesuvianite)

Grey-black idocrase is a rare, heavy opaque ornamental variant. Its high SG and spot RI 1.71 distinguish it from black jades and chalcedony.

Colour
grey
Transparency
Opaque
RI
1.713–1.718
SG
3.32–3.45
Mohs
6.5
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