Anhydrous tungstate, scheelite group, the tetragonal paramorph of raspite, which is monoclinic; forms a series with wulfenite
Specific gravity: 8.34
Hardness: 2½ to 3
Colour: Reddish brown, brown, yellowish grey, smoky-grey, grey-brown, straw-yellow, lemon-yellow, orange-yellow, red or green (rare)
Solubility: Decomposed by hydrochloric acid with the separation of yellow tungstic acid (Mindat)
Melting Point: 1,123oC
Common impurities: Mo
Stolzite is an uncommon mineral in the oxidised zone of hydrothermal tungsten-bearing lead deposits, associated
with raspite, cerussite,
anglesite, pyromorphite and
At Broken Hill, New South Wales, Australia, stolzite is extremely rare, but it has been found with anglesite (AJM 3.1.66 ).
At the Kara mine, Tasmania, Australia, stolzite has been found in a vesuvianite - pyroxene - magnetite - andradite skarn in pockets with mimetite and cerussite, on quartz, scheelite, andradite and epidote (AJM 13.1.50).
At the Sumidoro mine, near Mariana, Minas Gerais, Brazil, stolzite occurs with raspite (Dana).
At the Cariboo District, British Columbia, Canada, stolzite occurs with scheelite and hydrokenoelsmoreite variety ferritungstite (Dana).
The type locality is at Zinnwald, Ore Mountains, Europe.
At the Sainte Lucie mine, Lozere, France, fine specimens of stolzite to several cm in length have been found in vugs in galena - quartz veins associated with cerussite and also with pyromorphite. The country rocks are mica-poor quartzitic gneisses containing scheelite (Minrec 42.1.9-32).
At Neudorf, Harzgerode mining district, Harz, Saxony-Anhalt, Germany, stolzite occurs as coatings over corroded wolframite, and sometimes as an almost complete replacement of wolframite crystals embedded in quartz (Minrec 43.1.45).
At the Clara Mine, Oberwolfach, Ortenaukreis, Freiburg, Baden-Württemberg, Germany, stolzite is not rare, and it often forms a solid solution with wulfenite (R&M 90.1.48).
At the Erongo mountains, Karibib, Erongo Region, Namibia, rare microcrystals of stolzite have been found on orthoclase (Minrec 37.5.450).
At Tsumeb, Oshikoto Region, Namibia, stolzite has been found as crystals to 2.5 cm on tennantite, as crystals to 1 mm on a crust of tiny beudantite crystals, associated with chalcocite, on quartz and on hedyphane (R&M 94.1.79-80).
At the Cligga mine, Perranzabuloe, Cornwall, England, United Kingdom, rare supergene stolzite, raspite and philipsbornite occur with partly oxidised galena on a few small specimens from a wolframite-bearing quartz vein. The stolzite has been found associated with philipsbornite and plumbogummite in a small cavity (Mines & Minerals 34.29-32).
At the Primos Mine, Dragoon, Cochise Mining District, Little Dragoon Mountains, Cochise County, Arizona, USA, two specimens of millimeter sized stolzite crystals have been found on the dump of the Boericke or Primos mine. They came from vugs in a quartz vein which contains chalcopyrite, sphalerite, hübnerite, scheelite, fluorite and galena (AM 26.429).
At the Reef Mine, Huachuca mountains, south of Tombstone, Cochise county, Arizona, USA, stolzite crystals have been found implanted on the walls of cavities in vein quartz from which sulphides have been weathered out. Elsewhere the vein contains scheelite, as well as galena, chalcopyrite, pyrite and limonite (AM 26.429).
Near Miami, Gila county, Arizona, USA, stolzite containing about 9 per cent MoO3 occurs in cavities in quartz and disseminated in limonite (AM 43.156).
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