Smaltite

Smaltite is a variety of the mineral skutterudite consisting of cobalt, iron, nickel, and arsenide.

The color is tin-white to steel-grey, with a metallic luster; the streak is greyish black.

The cobalt is partly replaced by iron and nickel, and as the latter increases in amount there is a passage to the isomorphous species chloanthite (NiAs2).

[1] Smaltite occurs in veins with ores of cobalt, nickel, copper and silver.

The name smaltite was given by F. S. Beudant in 1832 because the mineral was used in the preparation of smalt for producing a blue color in porcelain and glass.