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Variety · Silicate

Demantoid

Ca₃Fe₂(SiO₄)₃

Brilliant green andradite — out-sparkles diamond; prized 'horsetail' inclusions.

Hardness6.5–7
Crystal systemCubic
ClassSilicate
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Demantoid specimen

Garnet: demantoid — Photo: Lech Darski · CC BY-SA 4.0

Demantoid

The vivid-green chromium-colored variety of andradite garnet — 'demantoid' means diamond-like, for its exceptional fire.

Intro adapted from Wikipedia (CC BY-SA).

Demantoid is a mineral variety of Andradite, with the chemical formula Ca₃Fe₂(SiO₄)₃.

It crystallizes in the cubic crystal system.

Key properties: Mohs hardness 6.5–7; typically green.

Collections: Gemstones, Rare & Remarkable.

Index entry. This entry combines official IMA/RRUFF species data with published physical-property data and a Wikipedia introduction — a full written entry hasn’t been published yet. Browse more D minerals or help write this entry.