Deposits of bauxite ores near aluminum smelters often possess an excessively high percentage of silica. Development of such high-silica ores would be benefi cial to alumina producers. Therefore, unique industrial and operational experience in the fi eld of high-silica bauxite processing was gained at the R u s s i a n N a t i o n a l A l u m i n i u m -Magnesium Institute, St. Petersburg, pilot plant with the consecutive extraction of silica and alumina from low-grade ores. This article describes the chemistry, processing-unit operations, and results obtained from this process.