PLATTNERITE

    Class : Oxides and hydroxides
    Subclass : Oxides
    Crystal system : Tetragonal
    Chemistry : PbO2
    Rarity : Uncommon

Plattnerite is an uncommon oxide from the oxidation zones of lead deposits. Its formation conditions seem even more drastic than those of massicot or minium : they require a strong desert climate, a high pH, and a strong oxidation-reduction potential. It was named in honor of Karl Friedrich Plattner; Professor of Metallurgy at the University of Freiberg (Germany). The crystals are small, elongated shiny black prisms, sometimes twinned, measuring up to 5 mm. But this mineral more readily constitutes fibrous nodular or botryoidal masses, with a zoned concentric texture, black to dark brown in color.

Main photo : Plattnerite from Preguiça Mine, Sobral da Adiça, Moura, Beja, Portugal © Pedro Alves

Plattnerite from Ojuela Mine, Mapimí, Durango, Mexico © G. Franz Zöll
Plattnerite from Trevasco, Lombardy, Italy © Enrico Bonacina
Plattnerite from Blanchard Mine, New-Mexico, USA © Jerry Cone
Twinned plattnerite from Preguiça Mine, Sobral da Adiça, Portugal © Pedro Alves

Plattnerite in the World

Plattnerite is known in the lead-zinciferous deposits of the Iranian desert, notably at Dareeh-Zandjir, near Yazd, where plattnerite develops considerably and covers thick encrustations on the carbonates of the deposit (calcite, cerussite, hydrozincite, etc...). Plattnerite constitutes large botryoidal masses in the lead deposits of Idaho (Coeur d'Alene, Morning...), and still remains common in the deposits of Nevada, New Mexico and Arizona. Among Mexican deposits, the famous Ojuela mine, near Mapimi, yields sporadic crystals in limonite geodes. In Europe, the gossans of the Scottish lead veins of Leadhills and Wanlockhead gave interesting crystals which made it possible in 1837 to define the species.

Plattnerite in France

In France, plattnerite is reported at Mas d'Alary (Hérault), at Cap Garonne (Var) and at the Grand Clot mine (Hautes-Alpes).

Twinning

Contact and penetration twins are known on {011}.

Fakes and treatments

No fakes listed for this mineral species.


Hardness : 5.5
Density : 9.56
Fracture : Fibrous to sub-conchoidal
Streak : Dark brown

TP : Translucent to opaque
RI : 2.250 to 2.350
Birefringence : 0.100
Optical character : Uniaxial -
Pleochroism : Low
Fluorescence : None

Solubility : Hydrochloric acid

Magnetism : NoneRadioactivity : None