Original paper
Brunogeierit, ein Germanium-Ferritspinell von Tsumeb
[Brunogeierite, a germanium-ferrite-spinel from Tsumeb]
Ottemann, Joachim; Nuber, Bernhard
Neues Jahrbuch für Mineralogie - Monatshefte Jg. 1972 Heft 6 (1972), p. 263 - 267
6 references
published: Aug 9, 1972
DOI: 10.1127/njmm/1972/1972/263
ArtNo. ESP156197206004, Price: 19.00 €
Kurzfassung
Im Zuge laufender Untersuchungen an problematischen Mineralbildungen von der Tsumeb-Mine in Südwestafrika (B. H. GEIER & J. OTTEMANN, 1970 und 1971) wurde ein bisher unbekanntes, oxidisches Germanium-Mineral festgestellt.
Abstract
The new germanium-mineral occurs in the lower partly oxidized zones of the Tsumeb orebody, South-West-Africa, mostly as rims encrusting tennantite which encloses renierite. These grains are almost always surrounded with stottite. The mineral is opaque and gray in colour. The hardness is much higher than that of tennantite and stottite. The reflectivity is lower than that of magnetite. Electron microprobe analyses of homogeneous grains from two polished sections gave GeO2 37.0; 40.5 and FeO (total iron) 63.8; 60.7 percent corresponding to: (GeFe2O4)x(Fe3O4)1-x, where x = 0.87; 0.95. The X-ray powder data are indexed on a cubic cell, a0 = 8.409 ± 0.004 Å, space group O 7h — Fd3m, Z = 8, G. calc. 5.51. The new mineral is a germanium-ferrite-spinel and was named for Dr. Bruno H. Geier, chief-mineralogist of the Tsumeb Corp., who has done very much to further the study of the mineral-paragenesis at Tsumeb.
Keywords
oxidized zone • grains • stottite • tennantite • electron microprobe • Tsumeb orebody • Mineralbildung • Untersuchung • Tsumeb-Mine • South-West-Africa • Südwestafrika