Melonite

Melonite is a telluride of nickel; it is a metallic mineral.

It is opaque and white to reddish-white in color, oxidizing in air to a brown tarnish.

It was first described from the Melones and Stanislaus mine in Calaveras County, California in 1866, by Frederick Augustus Genth.

Melonite occurs as trigonal crystals, which cleave in a (0001) direction.

It has a specific gravity of 7.72 and a hardness of 1–1.5 (very soft).

Melonite and Calaverite , Kambalda , Coolgardie Shire, Western Australia. Melonite is a rare nickel telluride. This is a showy, solid foliated mass of lustrous, slightly iridescent melonite with a bit of brassy, golden pyrite on one side from this major nickel producing area.
Melonite crystal structure (Wyckoff 1963), crystallographic standard alignment