Abstract: A method of producing an alumina bearing product in which the alumina is substantially soluble in cold alkali including the steps of contacting an aluminium bearing material with concentrated sulphuric acid containing 30 to 100 weight percent sulphuric acid, heat treating the acid and material to cause the acid to react with the material to form a substantially anhydrous hard product and decomposing the product by heat treatment to produce the alumina bearing product. The alumina values may be recovered from the resulting alumina bearing product using the known Bayer process. The process has particular application to non-bauxitic ores.