Bunsenite is the naturally occurring form of nickel(II) oxide, NiO. It occurs as rare dark green crystal coatings. It crystallizes in the cubic crystal system and occurs as well formed cubic, octahedral and dodecahedral crystals. It is a member of the periclase group.
It was first described in 1868 for a sample from a hydrothermal nickel from Johanngeorgenstadt , Saxony and named for German chemist Robert William Eberhard Bunsen Other occurrences include west of the Scotia talc mine near Bon Accord, Barberton , South Africa south of Kalgoorlie. The South African occurrence has evidence of thermal metamorphism of a nickel-rich meteorite It occurs associated with native bismuth , aerugite in Germany; and with liebenbergite , nickeloan serpentine, violarite and bonaccordite