STICHTITE: Argent Hill, Tasmania, Australia (specimen ~ 2 inches across). Photo © Joel E. Arem, PhD, FGA. Used with permission.
Stichtite is not facetable, but the pink color is quite striking in cabochons. Cut stones are especially beautiful when there are other minerals present to add splashes of green and yellow. This material somewhat resembles a pink, granular material from the USSR referred to as canasite.
| Data | Value |
|---|---|
| Name | Stichtite |
| Colors | Lilac to rose pink. |
| Stone Sizes | Massive material is sometime cut into cabochons, but the material is usually used to carve decorative objects such as ashtrays and bookends. The color is usually lilac to purplish, often veined with green serpentine, and the color combination is quite handsome. Blocks weighing several pounds are obtainable. |
| Formula | Mg6Cr2(CO3)(OH)16· 4H2O. |
| Fracture | Uneven |
| Hardness | 1.5-2.5. |
| Cleavage | Perfect 1 direction |
| Crystallography | Hexagonal (R) (trigonal). Massive, foliated, fibrous, lamellar, scaly. |
| Refractive Index | 1.518-1.545 |
| Birefringence | 0.027 |
| Luminescence | None. |
| Luminescence Present | No |
| Absorption Spectrum | Typical Cr spectrum: 3 lines in the red at 6655 to 6300. |
| Pleochroism | Light to dark red. |
| Optics | o = 1.545; e = 1.518. Uniaxial (-). Shadow edge seen at about 1.53. |
| Optic Sign | Uniaxial - |
| Luster | Pearly, waxy, greasy. |
| Specific Gravity | 2.16 (Quebec); 2.22 (South Africa). |
| Transparency | Translucent to opaque. |
Dimorph of Barbertonite.
Has a greasy feel.
Streak: White to lilac.
Optics: o=1.545; e =1.518.
Uniaxial (-).
Shadow edge seen at about 1.53.
Occurrence: In serpentine rocks, usually associated with chromite.
Black Lake, Quebec, Canada.
Dundas, Tasmania: mixed with green serpentine.
Transvaal, South Africa; Algeria.
Comments: Stichtite is not facetable, but the pink color is quite striking in cabochons. Cut stones are especially beautiful when there are other minerals present to add splashes of green and yellow. This material somewhat resembles a pink, granular material from the USSR referred to as canasite.
Name: After Robert Sticht of Tasmania, general manager of the Mt. Lyell Mining and Railway Co.
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