Duftite

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Duftite
Anglesite-Duftite-174037.jpg
Duftite from Tsumeb Mine, Tsumeb, Otjikoto Region, Namibia
General
Category Arsenate minerals
Formula
(repeating unit)
PbCuAsO4(OH)
IMA symbol Dft [1]
Strunz classification 8.BH.35
Dana classification41.5.1.4
Crystal system Orthorhombic
Crystal class Disphenoidal (222)
H-M symbol: (2 2 2)
Space group P212121
Unit cell a = 7.768(1), b = 9.211(1)
c = 5.999(1) [Å]; Z = 4
Identification
Formula mass 426.67 g/mol
ColorGreen, olive green or grey green. Generally zoned due to compositional variations.
Crystal habit Tiny crystals elongated along [001] with curved and rough faces, aggregated into crusts. Crystals may be pseudo-octahedral.
Cleavage Indistinct
Fracture Uneven to conchoidal
Mohs scale hardness4.5
Luster Vitreous on fracture surfaces and dull on crystal faces
Streak Pale green or white
Diaphaneity Crystals are transparent to translucent
Specific gravity 6.4 (measured), 6.60 (calculated)
Optical propertiesBiaxial (-), faint apple-green color (transmitted light)
Refractive index nα = 2.03–2.04, nβ = 2.06–2.08, nγ = 2.08–2.10
Birefringence δ = 0.06
2V angle Large
Dispersion r > v, perceptible
Solubility Readily soluble in acids [2]
Other characteristicsDecrepitates on heating. Not radioactive.
References [3] [4] [5]

Duftite is a relatively common arsenate mineral with the formula CuPb(AsO4)(OH), related to conichalcite. It is green and often forms botryoidal aggregates. It is a member of the adelite-descloizite Group, Conichalcite-Duftite Series. Duftite and conichalcite specimens from Tsumeb are commonly zoned in color 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. [6] It was named after Mining Councilor G Duft, Director of the Otavi Mine and Railroad Company, Tsumeb, Namibia. [2] The type locality is the Tsumeb Mine, Tsumeb, Otjikoto Region, Namibia.

Contents

Structure

The structure [7] 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 at the type locality, [2] and with bayldonite, segnitite, agardite and gartrellite at the Central Cobar Mines, New South Wales, Australia, where some pseudomorphs of duftite after mimetite have also found. [8] It occurs in association with olivenite, mottramite, azurite, malachite, wulfenite and calcite in the Tsumeb, Namibia deposit. It occurs with bayldonite, beudantite, mimetite and cerussite in the Cap Garonne mine, France. [5]

Duftite on cerussite, Tsumeb mine, Namibia (size: 6 x 5 x 3 cm) Duftite-Cerussite-174182.jpg
Duftite on cerussite, Tsumeb mine, Namibia (size: 6 × 5 × 3 cm)

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 US and Zimbabwe. [4]

Related Research Articles

<span class="mw-page-title-main">Wulfenite</span> Molybdate mineral

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".

<span class="mw-page-title-main">Mimetite</span> Lead arsenate chloride mineral

Mimetite is a lead arsenate chloride mineral (Pb5(AsO4)3Cl) which forms as a secondary mineral in lead deposits, usually by the oxidation of galena and arsenopyrite. The name derives from the Greek Μιμητής mimetes, meaning "imitator" and refers to mimetite's resemblance to the mineral pyromorphite. This resemblance is not coincidental, as mimetite forms a mineral series with pyromorphite (Pb5(PO4)3Cl) and with vanadinite (Pb5(VO4)3Cl). Notable occurrences are Mapimi, Durango, Mexico and Tsumeb, Namibia.

<span class="mw-page-title-main">Austinite</span> Arsenate mineral

Austinite is a member of the adelite-descloizite group, adelite subgroup, the zinc (Zn) end member of the copper-Zn series with conichalcite. It is the zinc analogue of cobaltaustinite and nickelaustinite. At one time “brickerite” was thought to be a different species, but it is now considered to be identical to austinite. Austinite is named in honour of Austin Flint Rogers (1877–1957), American mineralogist from Stanford University, California, US.

<span class="mw-page-title-main">Vauquelinite</span>

Vauquelinite is a complex mineral with the formula CuPb2(CrO4)(PO4)(OH) making it a combined chromate and phosphate of copper and lead. It forms a series with the arsenate mineral fornacite.

<span class="mw-page-title-main">Arthurite</span>

Arthurite is a mineral composed of divalent copper and iron ions in combination with trivalent arsenate, phosphate and sulfate ions with hydrogen and oxygen. Initially discovered by Sir Arthur Russell in 1954 at Hingston Down Consols mine in Calstock, Cornwall, England, arthurite is formed as a resultant mineral in the oxidation region of some copper deposits by the variation of enargite or arsenopyrite. The chemical formula of Arthurite is CuFe23+(AsO4,PO4,SO4)2(O,OH)2·4H2O.

<span class="mw-page-title-main">Conichalcite</span> Arsenate mineral

Conichalcite, CaCu(AsO4)(OH), is a relatively common arsenate mineral related to duftite (PbCu(AsO4)(OH)). 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.

<span class="mw-page-title-main">Ashburtonite</span>

Ashburtonite is a rare lead copper silicate-bicarbonate mineral with formula: HPb4Cu2+4Si4O12(HCO3)4(OH)4Cl.

<span class="mw-page-title-main">Plumbogummite</span> Alunite supergroup, phosphate mineral

Plumbogummite is a rare secondary lead phosphate mineral, belonging to the alunite supergroup of minerals, crandallite subgroup. Some other members of this subgroup are:

<span class="mw-page-title-main">Lavendulan</span>

Lavendulan is an uncommon copper arsenate mineral, known for its characteristic intense electric blue colour. It belongs to the lavendulan group, which has four members:

<span class="mw-page-title-main">Cornubite</span> Copper arsenate mineral

Cornubite is a rare secondary copper arsenate mineral with formula: Cu5(AsO4)2(OH)4. It was first described for its discovery in 1958 in Wheal Carpenter, Gwinear, Cornwall, England, UK. The name is from Cornubia, the medieval Latin name for Cornwall. It is a dimorph of cornwallite, and the arsenic analogue of pseudomalachite.

<span class="mw-page-title-main">Beudantite</span> Secondary mineral of the alunite group

Beudandite is a secondary mineral occurring in the oxidized zones of polymetallic deposits. It is a lead, iron, arsenate, sulfate with endmember formula: PbFe3(OH)6SO4AsO4.

<span class="mw-page-title-main">Tsumebite</span>

Tsumebite is a rare phosphate mineral named in 1912 after the locality where it was first found, the Tsumeb mine in Namibia, well known to mineral collectors for the wide range of minerals found there. Tsumebite is a compound phosphate and sulfate of lead and copper, with hydroxyl, formula Pb2Cu(PO4)(SO4)(OH). There is a similar mineral called arsentsumebite, where the phosphate group PO4 is replaced by the arsenate group AsO4, giving the formula Pb2Cu(AsO4)(SO4)(OH). Both minerals are members of the brackebuschite group.

<span class="mw-page-title-main">Warikahnite</span> Rare zinc arsenate mineral

Warikahnite is a rare zinc arsenate mineral of the triclinic crystal system with Hermann- Mauguin notation 1, belonging to the space group P1. It occurs in the Tsumeb mine in Namibia on corroded tennantite in the second oxidation zone under hydrothermal conditions in a dolomite-hosted polymetallic ore deposit. It is associated with adamite, stranskiite, koritnigite, claudetite, tsumcorite, and ludlockite. The origin of discovery was in a dolomite ore formation within an oxidized hydrothermal zone, in the E9 pillar, 31st level of the Tsumeb Mine in Namibia, Southwest Africa. It has also been found at Lavrion, Greece and Plaka, Greece as microscopic white needles.

<span class="mw-page-title-main">Tsumcorite</span>

Tsumcorite is a rare hydrated lead arsenate mineral that was discovered in 1971, and reported by Geier, Kautz and Muller. It was named after the TSUMeb CORporation mine at Tsumeb, in Namibia, in recognition of the Corporation's support for mineralogical investigations of the orebody at its Mineral Research Laboratory.

<span class="mw-page-title-main">Hidalgoite</span> Mineral of the beudantite group

Hidalgoite, PbAl3(AsO4)(SO4)(OH)4, is a rare member of the beudantite group and is usually classified as part of the alunite family. It was named after the place where it was first discovered, the Zimapán mining district, Hidalgo, Mexico. At Hidalgo where it was initially discovered, it was found as dense white masses in alternating dikes of quartz latite and quartz monzonite alongside other secondary minerals such as sphalerite, arsenopyrite, cerussite and trace amounts of angelsite and alamosite, it was then rediscovered at other locations such as Australia where it occurs on oxidized shear zones above greywacke shales especially on the anticline prospects of the area, and on fine grained quartz-spessartine rocks in Broken Hill, Australia. Hidalgoite specimens are usually associated with copper minerals, clay minerals, iron oxides and polymetallic sulfides in occurrence.

<span class="mw-page-title-main">Carminite</span> Anhydrous arsenate mineral containing hydroxyl

Carminite (PbFe3+2(AsO4)2(OH)2) is an anhydrous arsenate mineral containing hydroxyl. It is a rare secondary mineral that is structurally related to palermoite (Li2SrAl4(PO4)4(OH)4). Sewardite (CaFe3+2(AsO4)2(OH)2) is an analogue of carminite, with calcium in sewardite in place of the lead in carminite. Mawbyite is a dimorph (same formula, different structure) of carminite; mawbyite is monoclinic and carminite is orthorhombic. It has a molar mass of 639.87 g. It was discovered in 1850 and named for the characteristic carmine colour.

<span class="mw-page-title-main">Mottramite</span>

Mottramite is an orthorhombic anhydrous vanadate hydroxide mineral, PbCu(VO4)(OH), at the copper end of the descloizite subgroup. It was formerly called cuprodescloizite or psittacinite (this mineral characterized in 1868 by Frederick Augustus Genth). Duhamelite is a calcium- and bismuth-bearing variety of mottramite, typically with acicular habit.

<span class="mw-page-title-main">Minrecordite</span>

Minrecordite, CaZn(CO3)2, is a very rare mineral belonging to the dolomite group, the member with Ca and Zn. It was discovered, associated with dioptase, in a specimen from the Tsumeb mine (Namibia), which is consequently its type locality. Its name is a tribute to The Mineralogical Record magazine, representing the collaboration between professional and amateur mineralogists. In this locality it is associated primarily with dioptase, and less frequently with duftite, calcite and malachite. It is a rare mineral, which has been found only in a few deposits in the world. In addition to the type locality, it appears in the Preguiça mine, in Moura, district of Beja (Portugal).

<span class="mw-page-title-main">Arsendescloizite</span> Lead-zinc mineral

Arsendescloizite is a lead-zinc mineral, approved by the IMA in 1982. It is an arsenate analog of descloizite. Its first description was published in 1982.

Gallobeudantite is a secondary, Gallium-bearing mineral of beudantite, where the Iron is replaced with Gallium, a rare-earth metal. It was first described as a distinct mineral by Jambor et al in 1996. Specific Gallium minerals are generally rare and Gallium itself is usually obtained as a by-product during the processing of the ores of other metals. In particular, the main source material for Gallium is bauxite, a key ore of aluminium. However, Gallobeudantite is too rare to be of economic value. Its main interest is academic and also among mineral collectors.

References

  1. Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi: 10.1180/mgm.2021.43 . S2CID   235729616.
  2. 1 2 3 Wherry ET, Foshag WF (1921). "New mineral names" (PDF). American Mineralogist. 6: 140–141.
  3. Duftite. Webmineral.com. Retrieved on 2011-10-10.
  4. 1 2 Duftite. Mindat.org
  5. 1 2 Duftite. (PDF) Handbook of Mineralogy
  6. Jambor, J L, Owens, D R and Dutrizac, J E (1980). "Solid solution in the adelite group of arsenates" (PDF). Canadian Mineralogist. 18: 191–195.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  7. Kharisun; Max R. Taylor; D. J. M. Bevan; Allan Pring (1998). "The crystal chemistry of duftite, PbCuAsO4(OH) and the beta-duftite problem" (PDF). Mineralogical Magazine. 62 (1): 121–130. Bibcode:1998MinM...62..121K. doi:10.1180/002646198547413. S2CID   98680784.
  8. Australian Journal of Mineralogy. 11 (2): 79.{{cite journal}}: Missing or empty |title= (help)

Bibliography