Skorpionite and Tarbuttite from the Skorpion Mine, Namibia

Contributed by: Michael Crawford
Date: Jul 14th, 2025
Locality: Skorpion Mine, Rosh Pinah, Oranjemund Constituency, ?Karas Region, Namibia (See on Mindat)
Size: 3.5 x 4 cm

Description:
This specimen originates from the Skorpion Mine located in Rosh Pinah, Karas Region, Namibia. The zinc deposit at Skorpion Mine developed through the oxidation of sulfide ores by circulating meteoric waters, followed by mineral precipitation within a paleochannel. As a result, this specimen comprises secondary minerals precipitated from these meteoric waters, including pale green tarbuttite (Zn?(PO?)(OH)), skorpionite (Ca?Zn?(PO?)?(CO?)(OH)? · H?O), and hemimorphite (Zn?Si?O?(OH)? · H?O). Notably, the Skorpion Mine serves as the type locality for skorpionite.

Clear, acicular crystals of skorpionite are present within a vug in the tarbuttite matrix, accompanied by small hemimorphite crystals both inside and surrounding the vug. Two sets of images depict the specimen: the first shows the entire piece, while the second provides a detailed view of the vug containing skorpionite. The close-up images offer the best visibility of skorpionite and hemimorphite crystals.
Under ultraviolet illumination, the tarbuttite displays orange fluorescence under longwave and midwave UV, skorpionite exhibits yellow fluorescence under midwave and shortwave UV, and hemimorphite emits a light blue fluorescence under shortwave UV.

The emission spectrum for tarbuttite under longwave UV shows a broad peak near 569 nm; however, available literature does not specify potential activators responsible for this fluorescence. Additionally, the intensity of skorpionite fluorescence was insufficient to obtain a reliable emission spectrum.