TEALLITE

    Class : Sulfides and sulfosalts
    Subclass : Sulfides
    Crystal system : Orthorhombic
    Chemistry : PbSnS2
    Rarity : Very rare

Teallite is an extremely rare lead and tin sulfide. It is one of those minerals called "Bolivian" because it was long known exclusively in Bolivian tin veins, where it accompanies cassiterite, pyrite, galena, stannite and often two other typical minerals : franckeite and cylindrite. It was named in honor of Jethro Justinian Harris Teall, Director of the Geological Survey of Great Britain and Ireland. Teallite forms elongated, flexuous, centimeter-sized lamellar crystals, quite similar to those of molybdenite, gray-black in color, commonly gathered in lamellar aggregates. It is a mineral that tarnishes in the air with the appearance of iridescence. It constitutes an important tin ore in several Bolivian mines.

Main photo : Teallite from Carguaicollo Mine, Potosi, Bolivia © Eugene & Sharon Cisneros

Teallite in the World

Teallite is present in many Bolivian tin mines (districts of Montserrate, Colquechaca, Huanuni...), from where the most beautiful known samples come. However, it is reported as a mineralogical rarity in several mines outside Bolivia, as well as in the Ivigtut pegmatite (Greenland).

Right photo : Teallite from Carguaicollo Mine, Potosi, Bolivia © John Sobolewski


Teallite in France

Teallite is not present in the French underground.

Twinning

Twinning is only observable in polished section.

Fakes and treatments

No fakes listed for this mineral species.


Hardness : 1.5 to 2
Density : 6.36
Fracture : Undetermined
Streak : Black

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

Solubility : -

Magnetism : NoneRadioactivity : None