JDMISGem Reference
Quartz · Chalcedony

Red Chalcedony (Carnelian/Sard)

Red Chalcedony (Carnelian/Sard) — Chalcedony

Carnelian and sard are the iron-stained reds of the chalcedony family, warm and translucent with a waxy glow. Most market material is heated brown chalcedony, a stable and accepted treatment.

Colour
red
Transparency
Translucent
RI
1.530–1.539
SG
2.55–2.70
Mohs
6.5–7.0
Birthstone
March · August · May · July
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