DUFTITE

    Class : Phosphates, arsenates, vanadates
    Subclass : Anhydrous arsenates
    Crystal system : Orthorhombic
    Chemistry : PbCu(AsO4)(OH)
    Rarity : Uncommon

Duftite is an uncommon lead and copper arsenate from the oxidation zones of base metal deposits. It was named in honor of G. Duft, director of the Tsumeb mine (Namibia), where the mineral was discovered. The crystals are pseudo-octahedral or elongated, often rough and coarse, and do not exceed 5 mm. Duftite is most common in microcrystalline aggregates and encrustations, colored in varying shades of green. It is associated with many other secondary minerals of lead and/or copper, notably arsenates and carbonates.

Main photo : Duftite from Point 8.0, Borstein, Reichenbach, Lautertal, Hesse, Germany © Stephan Wolfsried

Duftite on calcite from Tsumeb, Namibia © Neal Luppescu
Duftite pseudomorph after wulfenite from Tsumeb, Namibia © Rob Lavinsky
Duftite from Tsumeb, Namibia © Stephan Wolfsried
Duftite from Cap Garonne, Var, France © Pascal Chollet

Duftite in the World

The "large" 5 mm duftite crystals come from the Mount Bonnie deposit (Australia), this country also having other duftite localities. Tsumeb produced duftite in abundance, but the 4 mm crystals are mimetite pseudomorphs. Duftite is also present in England (Cumbria and Cornwall), in the large Moroccan lead deposit of Touissit, and at Mapimi (Mexico), among others.

Duftite in France

In France, duftite is reported in several small copper deposits, notably at Cap Garonne (Var), Chessy (Rhône), Giromagny (Territoire-de-Belfort), Ste-Marie-aux-Mines (Haut-Rhin), Villefranche -de-Rouergue (Aveyron), etc...

Twinning

No twin known for this mineral species.

Fakes and treatments

No fake listed for this mineral species.


Hardness : 4.5
Density : 6.12
Fracture : Conchoidal ti sub-conchoidal
Streak : Green to white

TP : Translucent to transparent
RI : 2.030 to 2.100
Birefringence : 0.050 to 0.060
Optical character : Biaxial -
Pleochroism : None
Fluorescence : None

Solubility : -


Magnetism : None
Radioactivity : None