Wulfenite

Specimen of Wulfenite Wulfenite is a very collectible mineral. The species is unusual enough for you to take note, when it occurs at a deposit, but not so rare that it is very difficult to get hold of. It occurs in a wide range of colours, habits, and associations, it forms very attractive specimens, and Bideaux (1972) observed it as one of the most popular species in competitive exhibits at mineral shows.
It commonly occurs in the upper oxidation zone of lead deposits, particularly in arid areas. Particularly Arizona and Mexico have produced an incredible number of specimens from numerous localities. The Red Lead Mine in Arizona is famous for bright orange-red and red crystals, but very similar material and at least as good, albeit far less abundant occurs at the Tchah Mille mine near Anarak in Iran. Tsumeb in Namibia is often praised for superb Wulfenite crystals, and indeed they are often magnificent; the colour is often a bit dull, though the habit and association very varied, but really good Tsumeb specimens are actually quite rare. The Cryolite deposit, Ivigtut, in Greenland should be mentioned as an exotic Wulfenite deposit - the crystals are invariably small, but interesting because this is not a standard 'lead mine'. Sure Galena occurs, but the deposit as such carries rare and unusual fluoro-aluminates, intruded in a granite. The Wulfenite crystals obviously formed 'late' and are probably hydrothermal, but it is still an extraordinary occurrence.
The type locality is Bleiberg ('Lead Mountain') in Kärnten (Carinthia), Austria, from the mineral was described by the Jesuit abbot Franz Xaver Wulfen (1728-1805) in his 1785 treatise "Vom Kärntnerischen Bleispat" [On Carinthian Lead Spar], though the name Wulfenite was coined by Haidinger in 1845. Naming minerals for people did not start until 1792, and earlier names were often quite descriptive and utilitarian. The famous German mineralogist Werner applied the term "Gelbbleierz" [Yellow Lead Ore] to Wulfenite, characterising it as an ore and describing it by the yellowish brown colour, that predominates in Bleiberg and other European deposits. Most Wulfenite occurs as flat, tabular, square crystals, where the corners are often 'cut off,' but it is also known as squat bipyramids, and even elongate, tetragonal spindles (e.g., Ivigtut). Pure Wulfenite is colourless, and colourless, greyish or whitish crystals do occur, but are actually fairly rare. Most specimens are yellowish, brownish, blackish or even the highly desired red and orange.
Duftite, Galena, and Quartz are known to form pseudomorphs after Wulfenite, whereas Wulfenite forms pseudomorphs after Calcite, Cerussite, Mimetite, and Pyromorphite. Our records indicate that Wulfenite from a range of deposits occurs on specimens that also carry one or more of the following minerals: Barite, Brochantite, Calcite, Carnotite, Cerussite, Chalcopyrite, Coronadite, Creaseyite, Cuprite, Cuprosklodowskite, Demesmaekerite, Digenite var. Se-Digenite, Dolomite, Enargite, Fluorite, Galena, Gearksutite, Goethite, Guilleminite, Hemimorphite, Hetaerolite, Kasolite, Malachite, Mimetite, Molybdofornacite, Mottramite, Muscovite var. Sericite, Pachnolite, Phosphuranylite, Pyrite, Pyrolusite, Quartz, Ralstonite, Siderite, Stannite, Stolzite, Tennantite, Thomsenolite, Topaz, Torbernite, Vanadinite, and Vanadinite var. Endlichite.

Specimen Handling

Wulfenite is for all practical purposes stable in a normal household environment. It is not harmed by light, changes in temperature in the normal comfort range, or known to decompose. Wulfenite specimens are often very fragile and should be handled with great care, and preferably touched and moved as little as possible. Wulfenite is not appreciably soluble in water.

Bibliography

Anthony, John Williams, Sidney A. Williams, Richard A. Bideaux & Raymond W. Grant. 1995. Mineralogy of Arizona, 3rd ed.
Bancroft, Peter. 1984. Gem & Crystal Treasures.
Bideaux, Richard A. 1972. The collector. Mineralogical Record, 3(4), 148-150, 182-183
Blackburn, William H. & William H. Dennen. 1997. Encyclopedia of mineral names. Canadian Mineralogist, special publication 1.
Gaines, Richard W., H. Catherine W. Skinner, Eugene E. Foord, Brian Mason, Abraham Rosenzweig & Vandall T. King. 1997. Dana's new mineralogy: the system of mineralogy of James Dwight Dana and Edward Salisbury Dana, 8th ed.
Gebhard, Georg. 1991. Tsumeb, eine deutsch-afrikanische Geschichte.
Gebhard, Georg. 1999. Tsumeb, a unique mineral locality.
Hintze, Carl (ed.) 1916-1929. Handbuch der Mineralogie, vol. 1, section 3, part 1.
Noe-Nygaard, Arne. 1966. Mineralogi, 3rd ed.
Palache, Charles, Harry Berman & Clifford Frondel. 1951. The system of mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, 7th ed. Vol. 2.
Panczner, William D. 1987. Minerals of Mexico.
Ramdohr, Paul & Hugo Strunz. 1980. Klockmann's Lehrbuch der Mineralogie, 16th ed.
Roberts, Willard Lincoln, Thomas J. Campbell & George Robert Rapp jr. 1990. Encyclopedia of Minerals 2nd ed.
Sinkankas, John. 1964. Mineralogy.
Williams, Sidney A. 1966. The significance of habit and morphology of Wulfenite. American Mineralogist 51(7), 1212-1217


This page is written and maintaned by Claus Hedegaard