Smaltite Schneeberg Germany (4.3x3.5cm) — Photo: Didier Descouens · CC BY-SA 3.0
Skutterudite
A cobalt arsenide with variable nickel and iron — an important ore in cobalt-nickel veins, named for Skuterud, Norway.
Intro adapted from Wikipedia (CC BY-SA).
Skutterudite is an IMA-recognized mineral species in the sulfide class, with the chemical formula CoAs₃.
It crystallizes in the cubic crystal system (space group Im3). It is a member of the Perovskite, Skutterudite structural group.
Key properties: Mohs hardness 5.5–6; specific gravity 6.5; Black streak; Metallic. R: (400) 55.3, (420) 56.0, (440) 56.4, (460) 56.6, (480) 56.4, (500) 56.1, (520) 55.7, (540) 55.3 luster.
IMA symbol Skt, grandfathered status — known before the IMA’s founding, named in 1845.
is typically found in medium- to high-temperature hydrothermal veins with other Ni–Co sulfide minerals.
It is found associated with Nickeline, cobaltite, arsenopyrite, silver, silver sulfosalts, bismuth, calcite, siderite, barite, quartz.
The name refers to the Norwegian locality at Skutterud.