A large tungsten deposit on the Krantzberg Mt (1714 m above sea-level), now abandoned. Located 19 km SW of Omaruru on Farm Pristelwitz. Presently, access is prohibited.
A greisen-hosted W ore deposit with minor F, Sn, Be, Bi, Mo, and Fe-Cu sulfides. The ores were localized through an episode of alteration-mineralization related to the emplacement and fractionation of the Erongo A-type granite; this H2O-poor, but B- and F-rich granite was intruded after the collapse of the Erongo caldera. Granite fractionation resulted in H+- and B-enriched fluids which metasomatized and mineralized the roof country rocks. Early-stage greisenization and the later sericitization were accompanied by the concentration of dominant wolframite, fluorite, beryl, and sulfides. This alteration-mineralization occurred along major lithological and structural breaks. Wolframite (ferberite) formed during a stage of high F activity in the hydrothermal system.
Refs.:
- Pirajno, F. & Schlogl, H. U. (1987): The alteration-mineralization of the Krantzberg tungsten deposit, South West Africa/Namibia. South Afr. J. Geol. 90, 499-508.
- Jahn, S. & Bast, R. (2006): Der Krantzberg bei Omaruru, Namibia, und die Mineralvorkommen in seiner Umgebung. Mineralien-Welt 17 (3), 32-48.
