stannite

As part of a mineralogical study of ores from between levels 29 and 34, Geier and Ottemann (1970a) listed six sulphide minerals from Tsumeb with unusual chemistry, containing various combinations of gallium, germanium, tin or vanadium. Two of these were tin minerals to which they assigned "working names"; the first they called feuremineral (later understood to be a Ge-bearing mawsonite). The second was called LU and described as a "stannite-like mineral".

Mineral LU was observed under the ore microscope as minute grains (to 0.5 mm) intimately intergrown with feuremineral [= mawsonite] as rare inclusions in tennantite. These intergrowths consist of cores of mineral LU rimmed by mawsonite. Electron microprobe analysis gave a composition of 31. 8 wt % S; 30.9 % Cu; 23.2 % Sn; 10.4 % Fe; 1.7 % Ge; 0.9 % Zn and 0.6 % As. Geier and Ottemann (1970a) concluded that mineral LU is a Ge-enriched stannite.

Lombaard et al. (1986) listed stannite as "very rare"; Hughes (1987) concurred that "germanium-stannite" is "very rare", while Gebhard (1999) considered it "rare".

bornite; chalcocite; chalcopyrite; galena; germanite; mawsonite; pyrite; sphalerite; tennantite-(Zn)