LITHIOPHORITE

    Class : Oxides and hydroxides
    Subclass : Hydroxides and hydrates
    Crystal system : Trigonal
    Chemistry : (Al,Li)MnO2(OH)2
    Rarity : Quite common


Lithiophorite is an oxide of manganese, aluminum and lithium (the latter does not seem to be an essential component). It is an essential constituent of "wad" or "psilomelanes", these black oxides which stain the fingers that we encounter in the supergene oxidation zone of manganese deposits, various manganiferous hydrothermal deposits (gold, lead, silver ...), sometimes banded iron formations and certain phosphate pegmatites. Lithiophorite is also a major component of certain lateritic soils. In its deposits, it is associated with numerous other manganese oxides (cryptomelane, braunite, etc...) and its rigorous identification requires the use of X-ray diffraction spectra. Its name derives from its chemical composition (lithium) and Greek pherein (to show). Lithiophorite very rarely occurs in hexagonal crystals ; it rather forms finely grained botryoidal masses, in scales or dendrites, from a bluish black to a matt black. It is locally an important manganese ore.

Main photo : Lithiophorite from Murzinskoe gold deposit, Krasnoshchyokovsky, Russia © Eugene & Sharon Cisneros

Lithiophorite in the World

The largest known crystals of lithiophorite measure 12 mm and come from Gloucester Farm, in the large manganese district of Postmasburg (South Africa). Aesthetic botryoidal masses were extracted from the pegmatite of Itatiaia (Minas Gerais, Brazil). In addition to these two occurrences which provided quality pieces, litthiophorite deposits are numerous but offer little mineralogical interest. They are known in particular in Germany (Schneeberg, Saalfeld, Saint-Andréasberg), in Australia (Pilbara, Kalgoorlie...) and in the United States (Charlottesville, Virginia).

Lithiophorite in France

In France, lithiophorite is reported on the Plateau d'Ambulla (Pyrénées-Orientales), in the Aure valley (Hautes-Pyrénées) in Echassières (Allier) as well as in several deposits in New Caledonia.

Right photo : Lithiophorite from Echassières, Allier, France © Pascal Chollet

Twinning

No twin known for this mineral species.

Fakes and treatments

No fakes recorded for this mineral species.



Hardness : 3
Density : Undetermined
Fracture : Undetermined
Streak : Black


TP : Opaque
RI : -
Birefringence : -
Optical character : -
Pleochroism : None
Fluorescence : None


Solubility : -

Magnetism : NoneRadioactivity : None