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For the iron chromium sulfide mineral see Daubréelite
CategoryOxide mineral
(repeating unit)
Strunz classification3.DC.25
Crystal systemTetragonal
Crystal classDitetragonal dipyramidal (4/mmm)
H-M symbol: (4/m 2/m 2/m)
Space groupP4/nmm
Unit cella = 3.85, c = 7.4 [Å]; Z = 2
ColorCreamy-white, grayish, yellowish-brown
Crystal habitCompact massive, columnar
Cleavage[{001}, perfect
TenacityVery plastic, sectile
Mohs scale hardness2-2.5
LusterGreasy, silky
DiaphaneityTransparent to translucent
Specific gravity6-6.5
Optical propertiesUniaxial (-)
Refractive indexnω = 2.150 nε = 1.910
Birefringenceδ = 0.240

Daubréeite is a rare bismuth oxohalide mineral with formula BiO(OH,Cl). It is a creamy-white to yellow-brown, soft, earthy clay–like mineral which crystallizes in the tetragonal crystal system. It is a member of the matlockite group.[1]

It was first described for an occurrence in the Constanicia mine, Tazna, Bolivia, in 1876.[4] It was named for French mineralogist Gabriel Auguste Daubrée (1814–1896).[1] At the Tanza location it occurs as a secondary mineral formed by the oxidation of native bismuth or bismuthinite. It occurs with clay minerals.[3] In addition to its discovery location it has also been reported from the Tintic District in the East Tintic Mountains of Juab County, Utah; in the Josephine Creek District of Josephine County, Oregon; in the Manhattan District of Nye County, Nevada; and the Rio Marina Mine on Elba, Italy.[1]


  1. ^ a b c d Daubréeite on Mindat
  2. ^ Daubréeite on Webmineral
  3. ^ a b Daubréeite in the Handbook of Mineralogy
  4. ^ Domeyko (1876). "Daubréite(oxychlorure de bismuth), espèce minérale nouvelle". Comptes Rendus de l'Académie des Sciences de Paris. 82: 922–923.