DETERMINATION of the digestibility pattern of the bauxite samples is the most important step towards the design of an integrated alumina plant principally based on Bayer's process. Of all the aluminous minerals, the trihydrate gibbsite is the most amenable to Caustic digestion, and diaspore the hardest to treat. Altekar and Mathadt proceeded to determine the mineralogical set-up of the Kolhapur bauxite. The samples were obtained by the senior
author from seventeen different pits dug to an average
depth of 17' in a 30-acre plateau on top of a 3,000' high hill near Udgcri. The deposit has been since estimated at 3'5 million tons of bauxite. The findings of the author were that the principal and predominant mineral of alum-inium is gibbsite and it was therefore predicted that its response to caustic treatment would be quite favourable. Thic paper records the results of detailed investigations concerning the digestion of the bauxit