Prograde andalusite in kyanite-bearing siliceous rocks in the Ilangwe Greenstone Belt, southeastern margin of the Kaapvaal Craton, South Africa.

Andalusite is found in kyanite-bearing siliceous rocks belonging to the Nondweni Group in the Ilangwe Greenstone Belt, along the southeastern margin of the Kaapvaal Craton. Textural relationships of the minerals indicate that kyanite growth post-dated and replaced pre-existing andalusite. The kyanite overgrowth is interpreted to result from tectonic loading associated with the tectonic emplacement of the Mesoproterozoic Natal Belt lithologies onto the Kaapvaal Craton. The andalusite probably grew in a thermal aureole during the emplacement of Archaean granitoids. [ABSTRACT FROM AUTHOR]