Duftite is a relatively common arsenate mineral

Arsenate mineral

Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the 3- anion group and, more rarely, other arsenates with anions like AsO32- or [AsO22]- . Arsenite minerals are much less common...

 with the formula CuPb(AsO₄)(OH), related to conichalcite

Conichalcite

Conichalcite, CaCu, is a relatively common arsenate mineral related to duftite . It is green, often botryoidal, and occurs in the oxidation zone of some metal deposits. It occurs with limonite, malachite, beudantite, adamite, cuproadamite, olivenite and smithsonite.- Formation :Conichalcite forms...

. It is green and often forms botryoidal aggregates. It is a member of the Adelite

Adelite

The rare mineral adelite, is a calcium, magnesium, arsenate with chemical formula CaMgAsO4OH. It forms a solid solution series with the vanadium bearing mineral gottlobite...

-Descloizite Group, Conichalcite-Duftite Series. Duftite and conichalcite specimens from Tsumeb are commonly zoned in colour and composition. Microprobe analyses and X-ray powder-diffraction studies indicate extensive substitution of Zn for Cu, and Ca for Pb in the duftite structure. This indicates a solid solution among conichalcite, CaCu(AsO₄ )(OH), austinite, CaZn(AsO₄)(OH) and duftite PbCu(AsO₄)(OH), all of them belonging to the adelite group of arsenates. It was named after Mining Councilor G Duft, Director of the Otavi Mine and Railroad Company, Tsumeb, Namibia. The type locality

Type locality (geology)

Type locality , also called type area or type locale, is the where a particular rock type, stratigraphic unit, fossil or mineral species is first identified....

 is the Tsumeb Mine, Tsumeb

Tsumeb

Tsumeb is a city of 15,000 inhabitants and the largest town in Oshikoto region in northern Namibia. Tsumeb is the home of the world-famous Tsumeb mine, and the "gateway to the north" of Namibia. It is the closest town to the Etosha National Park...

, Otjikoto Region, Namibia.

Structure

The structure is composed of chains of edge-sharing CuO₆ distorted octahedra parallel to the c axis. The chains are linked by AsO₄ tetrahedra and Pb atoms.

Environment

Duftite is an uncommon product of weathered sulfide ore deposits. It is associated with azurite

Azurite

Azurite is a soft, deep blue copper mineral produced by weathering of copper ore deposits. It is also known as Chessylite after the type locality at Chessy-les-Mines near Lyon, France...

 at the type locality, and with bayldonite, segnitite, agardite

Agardite

Agardite is a mineral group consisting of agardite-, agardite-, agardite-, and agardite-. They comprise a group of minerals that are hydrous hydrated arsenates of rare earth elements and copper, which contain variable amounts of calcium and sometimes lead...

 and gartrellite at the Central Cobar Mines, New South Wales, Australia, where some pseudomorphs of duftite after mimetite

Mimetite

Mimetite, whose name derives from the Greek Μιμητής mimethes, meaning "imitator", is an arsenate mineral which forms as a secondary mineral in lead deposits, usually by the oxidation of galena and arsenopyrite. The name is a reference to mimetite's resemblance to the mineral pyromorphite...

 have also found. It occurs in association with olivenite

Olivenite

Olivenite is a copper arsenate mineral, formula Cu2AsO4OH. It crystallizes in the monoclinic system , and is sometimes found in small brilliant crystals of simple prismatic habit terminated by domal faces...

, mottramite

Mottramite

Mottramite is an orthorhombic mineral, PbCu, at the copper end of the descloizite group. It was formerly called cuprodescloizite or psittacinite .-References:***...

, azurite

Azurite

Azurite is a soft, deep blue copper mineral produced by weathering of copper ore deposits. It is also known as Chessylite after the type locality at Chessy-les-Mines near Lyon, France...

, malachite

Malachite

Malachite is a copper carbonate mineral, with the formula Cu2CO32. This green-colored mineral crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses. Individual crystals are rare but do occur as slender to acicular prisms...

, wulfenite

Wulfenite

Wulfenite is a lead molybdate mineral with the formula PbMoO4. It can be most often found as thin tabular crystals with a bright orange-red to yellow-orange color, sometimes brown, although the color can be highly variable. In its yellow form it is sometimes called "yellow lead ore".It crystallizes...

 and calcite

Calcite

Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite. Aragonite will change to calcite at 380-470°C, and vaterite is even less stable.-Properties:...

 in the Tsumeb, Namibia deposite. It occurs with bayldonite

Bayldonite

Bayldonite is a rare secondary mineral with the chemical formula PbCu322H2O. It was first discovered in Penberthy Croft Mine, Cornwall, England, UK. It is named after its discoverer, John Bayldon....

, beudantite

Beudantite

Beudandite is a secondary mineral occurring in the oxidized zones of polymetallic deposits. It is a lead, iron, arsenate, sulfate with endmember formula: PbFe36SO4AsO4....

, mimetite

Mimetite

Mimetite, whose name derives from the Greek Μιμητής mimethes, meaning "imitator", is an arsenate mineral which forms as a secondary mineral in lead deposits, usually by the oxidation of galena and arsenopyrite. The name is a reference to mimetite's resemblance to the mineral pyromorphite...

 and cerussite

Cerussite

Cerussite is a mineral consisting of lead carbonate , and an important ore of lead. The name is from the Latin cerussa, white lead. Cerussa nativa was mentioned by Conrad Gessner in 1565, and in 1832 F. S. Beudant applied the name cruse to the mineral, whilst the present form, cerussite, is due to...

 in the Cap Garonne mine, France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

.

Distribution

Reported from Argentina, Australia, Austria, Chile, the Czech Republic, France, Germany, Greece, Italy, Japan, Mexico, Namibia, Poland, Portugal, Russia, South Africa, Spain, Switzerland, the UK, the USA and Zimbabwe.