Bunsenite (original) (raw)

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Bunsenite
Bunsenite with unknown colorless crystals from the collection of the „Verein zur Förderung der Lithothek“, Munich (collection number A022658). Field of view 1 mm. Locality: Kochhütte, Helbra, Mansfeld-Südharz, Saxony-Anhalt, Germany
General
Category Oxide mineral
Formula(repeating unit) NiO
IMA symbol Bus[1]
Strunz classification 4.AB.25
Crystal system Cubic
Crystal class Hexoctahedral (m3m) H–M symbol: (4/m 3 2/m)
Space group _F_m3m
Unit cell a = 4.1769 Å; Z = 4
Identification
Color Dark pistachio-green
Crystal habit Octahedral crystal coatings, also cube or dodecahedron forms
Twinning Observed
Cleavage None
Mohs scale hardness 5.5
Luster Vitreous
Streak Brownish-black
Diaphaneity Transparent
Specific gravity 6.898
Optical properties Isotropic
Refractive index n = 2.37
Other characteristics Very high relief
References [2][3][4][5]

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 nickeluranium vein from Johanngeorgenstadt, Ore Mountains, Saxony, Germany and named for German chemist Robert Bunsen (1811–1899).[3][5] Other occurrences include west of the Scotia talc mine near Bon Accord, Barberton district, Transvaal, South Africa and from Kambalda south of Kalgoorlie, Western Australia. The South African occurrence has evidence of thermal metamorphism of a nickel-rich meteorite.[4] It occurs associated with native bismuth, annabergite, aerugite, xanthiosite in Germany; and with liebenbergite, trevorite, nickeloan serpentine, nickeloan ludwigite, violarite, millerite, gaspeite, nimite and bonaccordite in the South African occurrence.[4]

  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ Mineralienatlas
  3. ^ a b Bunsenite on Mindat.org
  4. ^ a b c "Bunsenite in the Handbook of Mineralogy" (PDF). Archived from the original (PDF) on 2019-05-08. Retrieved 2014-01-25.
  5. ^ a b Bunsenite data on Webmineral