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Boulangerite

Boulangerite
Boulangerite-uri-41a.jpg
Boulangerite, covering a block of limestone
General
Category Sulfosalt minerals
Formula
(repeating unit)
Pb5Sb4S11
Strunz classification 2.HC.15
Crystal system Orthorhombic
Crystal class Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
Space group Pnam
Identification
Luster Metallic
Streak Black
References

Boulangerite is a sulfosalt mineral, lead antimony sulfide, formula Pb5Sb4S11. It was named in 1837 in honor of French mining engineer Charles Boulanger (1810–1849). It forms metallic grey orthorhombic crystals. Sometimes the crystals form a fine feathery mass which has been called plumosite. Boulangerite is used as a lead ore.


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Wikipedia

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