By Didier Descouens (Own work) [GFDL or CC-BY-SA-3.0-2.5-2.0-1.0], via Wikimedia Commons
Smaltite is a collectors oddity, cut only as cabochons. It is seldom seen in collections since it is not especially distinctive, with a color resembling other metallic sulfides and arsenides.
| Data | Value |
|---|---|
| Name | Smaltite |
| Is a Variety of | Skutterudite |
| Colors | Silver gray to tin white; may tarnish gray to iridescent. |
| Crystallography | Isometric. Crystals cubic to octahedral; massive. fine-grained. |
| Luster | Metallic. |
| Hardness | 5.5-6 |
| Fracture | Uneven to conchoidal |
| Specific Gravity | ~ 6.1. |
| Birefringence | None. |
| Cleavage | Distinct 2 directions |
| Stone Sizes | Cabochons could be cut to any size from massive material. |
| Luminescence | None. |
| Luminescence Present | No |
| Transparency | Opaque. |
| Phenomena | Iridescence. |
| Formula |
(Co,Ni)As3. Considered to be an arsenic-deficient Skutterudite. |
| Pleochroism |
None. |
Streak: Black.
Occurrence: Occurs in medium- to high-temperature veins, with Ni and Co minerals.
California; Colorado.
Cobalt district. Ontario and British Columbia, Canada.
Chile; Switzerland: Germany.
Comments: Smaltite is a collectors oddity, cut only as cabochons. It is seldom seen in collections since it is not especially distinctive, with a color resembling other metallic sulfides and arsenides.
Name: From its use as a source of cobalt for the pigment smalt, which is blue.
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