Melonite is a telluride of nickel; it is a metallic mineral. Its chemical formula is NiTe2. 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).