The search for aluminous ores, which was undertaken by the Bureau of Mines from April, 1974 to April, 1975 in compliance with Letter of Instruction Nos. 184 and 269, resulted in the discovery of new bauxite deposits in Samar Island, Philippines. These bauxite deposits are of the gibbsite-boehmite variety. They are located in limestone areas with characteristic karst topography. Large deposits are found in sinkholes and karsted surfaces of limestone. Indisputably, they have originated by terrestial or subaerial weathering of various rocks,.
transportation of the weathering products, high in alumina, and subsequent deposition in the sinkholes and karstic surfaces of limestone.