Bauxite Residuum Derived from Khondalite and Charnockite

Abstract

The bauxite deposits occurring amidst the Eastern Ghats overlie either the Khondalite or Charnockite group of rocks. Their frequency, however, is more on the khondalitic rocks. Gibbsite constitutes the main aluminous mineral in both the cases. Goethite is ubiquitous in the residuum derived from charnockitic rocks while hematite occurs in larger proportions in the others. Salient contrasts in the residuum derived from either of the two major rock types of the Eastern Ghats are described and their possible implications surmised.