biotite series

TSNB55

Species

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

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.

albite; almandine; anatase; anorthite; calcite; clinochlore; epidote; fayalite; fluorapatite; graphite; ilmenite; magnetite; microcline; montmorillonite; muscovite; orthoclase; quartz; rutile; talc (?); titanite; tourmaline supergroup; zircon