sulvanite

Geier and Ottemann (1970a) listed six sulphide minerals from Tsumeb (senso lato) with unusual chemistry, containing gallium, germanium, tin or vanadium. One of these minerals was a germanium-enriched sulvanite. Five of the six minerals were observed in specimens from between 29 and 34 levels; the sixth – sulvanite – was observed in mineralised material from "… two out-lying prospects of the Tsumeb mine" and not from the Tsumeb mine itself.

Geier (1973/74), however, later listed "Germanium-Sulvanite" containing " … almost 5 % germanium" as one of several minerals newly recognised at Tsumeb from between levels 20 and 34.

Ramdohr (1975, 1980) cited a personal communication from Bruno Geier confirming the recent discovery of "… distinct sulvanite" at Tsumeb.

Bartelke (1976) and Keller (1984) both cited Geier and Ottemann (1970a) in describing 3 mm aggregates of yellowish but rapidly-tarnishing sulvanite in copper ore but failed to note that this occurrence was not from the Tsumeb mine (see above).

Lombaard et al. (1986) confirmed the occurrence of sulvanite at Tsumeb but considered it "extremely rare"; Hughes (1987) also confirmed the occurrence and commented that sulvanite may originally have been mistaken for colusite by Geier (in unpublished TCL reports).

calcite; chalcocite; molybdenite; sphalerite