JDMISGem Reference
Man-made product · Plastic (gem imitation)

Plastic — Grey-Black

Plastic — Grey-Black — Plastic (gem imitation)

Moulded plastic imitating jet, black onyx and obsidian - exposed by heft, warmth, softness, bubbles and the hot-point reaction.

Colour
grey
Transparency
Transparent
RI
1.460–1.700
SG
1.05–1.55
Mohs
1.5–3.0
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