Title
biotite series
Crystal System
Monoclinic
Status at Tsumeb
Believed valid
Abundance
Somewhat rare
Distribution
Country rocks (kersantite, feldspathic sandstone)
Paragenesis
Rock-forming (igneous, detrital).
Type Locality
No
Entry Type
Species TSNB55
General Notes
Botha (1960) noted the presence of biotite as a component of Mulden Group arenites in the Tsumeb area; Hedberg (1979) considered that this biotite was exclusively rounded and detrital (in contrast to muscovite, which he believed to be of metamorphic origin, supported by its parallel alignment to a weakly developed cleavage (see also Hughes 1987).
Various authors confirm the presence of biotite in the feldspathic sandstone bodies (Söhnge 1964; Hughes 1987); curiously, however, biotite is omitted from the description of feldspathic sandstone by Lombaard et al. (1986).
Biotite also occurs as a component of the kersantite dykes that intersect the ore-body between surface and 20 Level (Söhnge 1964; Lombaard et al. 1986; Hughes 1987).
Please also refer to the notes on phlogopite.
Associated Minerals
albite; almandine; anatase; anorthite; calcite; clinochlore; epidote; fayalite; fluorapatite; graphite; ilmenite; magnetite; microcline; montmorillonite; muscovite; orthoclase; quartz; rutile; talc (?); titanite; tourmaline supergroup; zircon