Bauxite in Sarawak

Tropical weathering of various basic and intermediate igneous rocks has given rise to the bauxite deposits of western Sarawak. The pH of ground waters plays an important role in the genetic process. Some of the highest-grade material, such as the Munggu Belian deposits, has been formed from pyroxene andesite; other parent materials include gabbro, diorite, plagioclase amphibolite, and intensely altered andesitic and basaltic volcanic rocks. The bauxite consists principally of gibbsite, with varying amounts of quartz, kaolinitic clay minerals, and iron and titanium oxides.

This record provided courtesy of AGI/GeoRef.