muscovite

Botha (1960) noted the presence of both muscovite and biotite micas in Mulden Group arenites in the Tsumeb area. He believed the muscovite to be of metamorphic origin in contrast to the biotite which occurs as rounded grains interpreted as detrital in origin.

Hughes (1987) observed that coarse-grained muscovite in Mulden arenites shows no preferred orientation but contains inclusions of relict biotite, implying that it formed from the alteration of biotite. On the other hand, fine-grained white mica ("sericite") is aligned parallel to a weak metamorphic fabric, which is consistent with Botha’s (1960) interpretation.

Muscovite is present as an accessory mineral in the feldspathic sandstone which is derived from the Mulden arenites (Lombaard et al. 1986; Hughes 1987). Lombaard et al. (1986) noted that muscovite is a product of sericitisation of feldspars in the feldspathic sandstone.

albite; almandine; anorthite; anorthoroselite; biotite series; calcite; clinochlore; epidote; fluorapatite; graphite; ilmenite; kaolinite; magnetite; microcline; montmorillonite; orthoclase; quartz; rutile; tourmaline supergroup; zircon