These include arsentsumebite, tsumebite, corkite, fornacite, duftite, caledonite, kettnerite, linarite, leadhillite, brochantite, mimetite, pyromorphite, vanadinite and wulfenite.
5 mm) of calcian duftite were found associated with uncommon elongate white mimetite prisms (to 1 mm).
Goodchild, of the Scottish Geological Survey, found wulfenite there in 1875 but the locality only really became of interest to collectors in the 1950s following the reporting of a suite of rare supergene minerals including bayldonite, duftite
, beudantite, carminite, lindgrenite and stolzite (the first authenticated British occurrence).
Associated phases were bayldonite, duftite
, gartrellite, agardite, mimetite and various arsenic-bearing members of the jarosite supergroup.
Associated minerals are: chalcocite, wulfenite, duftite
" (calcian conichalcite), "cuproadamite" and olivenite.
Tsumeb has produced thousands of dioptase specimens containing sharply formed, translucent to transparent crystals to 5 cm, typically on white calcite or dolomite and occasionally associated with cerussite and duftite
3 mm) of dark red-brown duftite
, consisting of minute (0.
And I also saw a few fine specimens of azurite or cerussite (or both) on botryoidal duftite
from Touissit: a new one on me.
Like duftite, bindheimite has been found only in one specimen, as white earthy pseudomorphs after acicular crystals of lead sulphoantimonides.
Apple-green, earthy duftite associated with bindheimite has been found in a single specimen from the Tognetti quarry.
The mineralogy and geochemistry of this gossan have been described by Nickel (1982), who noted the occurrence of a number of secondary ore minerals including malachite, azurite, chrysocolla, pseudomalachite, cerussite, alunite, jarosite, plumbojarosite, osarizawaite, plumbogummite, duftite
, mimetite, fornacite, wulfenite, mottramite, iodargyrite, native silver and a silver-mercury amalgam.
Some superfine, enormous cerussites were sold before I got there, but when I arrived the room still held some excellent small fishtail cerussites from both the Tsumeb and Kombat mines, Namibia, some fine Tsumeb calcite rhombohedron specimens with green duftite
inclusions, a couple of super Tsumeb wulfenite thumbnails, and many rarities for the specialized specialist, e.