Ametrine
QuartzJewelryWiki Editorial·2 sources·Reviewed 2026-08-04
A single quartz crystal that is part amethyst and part citrine, split down the middle. Nearly all of it comes from one mine in Bolivia, and the two-tone effect is natural — the purple and yellow zones formed at different temperatures within the same crystal.
Properties
| Property | Value | Authority |
|---|---|---|
| Mohs hardness | 7 [1] | — |
| Specific gravity | 2.651 [1] | — |
| Chemical formula | SiO2 Read from the species entry, Quartz. [2] | — |
| Crystal system | Hexagonal (trigonal) [1] | — |
| Common treatments | GIA records that quartz may be irradiated and heated, and combination treatments are used to produce two-tone material. Bolivian natural ametrine shows a sharp, straight boundary between the zones. [1] | — |
| Suitability for daily wear | Very good, per IGS, and not heat-sensitive. At Mohs 7 it is fine for everyday wear. [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)