calcite (w. conichalcite-duftite)

conichalcite-duftite; dolomite

A single colourless, translucent rhombohedral calcite crystal (circa 25 mm) rests on a multi-layered and somewhat cavernous crust of pink and white dolomite. The dolomite is richly covered with spherules and sub-botryoidal crusts of dark-green conichalcite-duftite (XRD verified). 

The specimen was formerly in the collection of Franz Lammer (Austria), and was acquired by him in Tsumeb, apparently during a safari to Namibia in 1979, from a vendor that his label names simply as "Müller" (Exhibit 2).