Glaucodot

The first published reference to glaucodot at Tsumeb is by Bartelke (1976), citing a 1973 TCL report (unpublished) by Bruno Geier but, curiously, Geier (1973/74) made no mention of the mineral. Bartelke (1976) noted that it occurs as microscopic inclusions in sulphide ores visible only under the ore microscope.

Lombaard et al. (1986) listed glaucodot as an extremely rare mineral at Tsumeb. However, Hughes (1987) notes that Geier’s original identification was based on optical properties only. Hughes considered the occurrence questionable and suggested that verification is required.