Abstract:
The growth of gem quality metamorphic minerals is most likely in fluid rich systems, where growth rate exceed the rate of nucleation. This condition typically occurs when crystallizing is close to equilibrium. This communication discusses metasomatic growth of corundum crystals at the boundary between ultramafic and acidic granulites. The phase petrology of the formation of corundum at the Rupaha deposit is presented Corundum forms due to desilification of the acidic granulite during peak granulite facies.
