hermannroseite

Hermannroseite, IMA2010-006, was described from a specimen collected by TCL mineralogist Bruno Geier (# 16862), from East 49 Stope on 28 Level, in the second oxidation zone, probably in late 1967 (see below). The specimen was obtained from Geier’s heirs by Georg Gebhard and the new mineral was described by Schlüter et al. (2011) who named it for Professor Hermann Rose (1883-1976), who was head of the Mineralogical Institute at Hamburg University between 1922 and 1954. Type material is conserved at the Mineralogisches Museum, Universität Hamburg, Germany, specimen number (MMHH TS 637).

A small fragment from the type material is conserved in the Feinglos Collection at Harvard University (MGMH 2022.4.10393T). Feinglos’ datacard records that the specimen is "part of holotype from author (GG) [= Georg Gebhard] collected by B. Geier, 11-20-1967".

Hermannroseite is the phosphate analogue of conichalcite. It occurs with conichalcite, pseudomalachite and whitlockite lining a vug in hydroxylapatite which is stained black with amorphous manganese oxides. These minerals form a botryoidal crust in which conichalcite encloses alternating microcrystalline sequences of conichalcite, hermannroseite, hydroxylapatite, pseudomalachite and whitlockite (Schlüter et al. 2011). The hermannroseite forms green transparent microcrystals with a mean size of less than one micron.

conichalcite; hydroxylapatite; pseudomalachite; whitlockite