Sugilite
SugiliteJewelryWiki Editorial·2 sources·Reviewed 2026-08-04
An opaque purple stone that only entered the jewellery trade in the 1970s, when gem-quality material was found in South Africa. Good colour is intense magenta-violet; most of what is sold is duller and mottled with black.
Properties
| Property | Value | Authority |
|---|---|---|
| Mohs hardness | 6–6½ [1] | — |
| Specific gravity | 2.74–2.79 [2] | — |
| Chemical formula | KNa2(Fe3+,Mn3+,Al)2Li3Si12O30 [2] | — |
| Crystal system | Hexagonal [2] | — |
| Common treatments | Heat treatment, per IGS. [1] | — |
| Care cautions | Reasonably durable at 6–6½, but avoid ultrasonic cleaners and knocks. [1] | — |
Sources
- International Gem Society — gemstone articles — International Gem Society (IGS, gemstone information articles (gemsociety.org))
- Handbook of Mineralogy — Mineral Data Publishing / Mineralogical Society of America (Handbook of Mineralogy, Mineral Data Publishing)