corundum, ruby, sapphire, Sri Lanka.12, gems

Sri Lanka is famous for having one of the greatest varieties of gemstones, all of which occur in placer deposits. Interestingly, the original host rocks have not yet been discovered. The geology consists largely of Precambrian formations, which can be divided into three major groups: the Highland Group, Southwest Group, and Vijayan Group. The principal gemstone-producing areas are the Ratnapura region in Sabaragamuwa Province, the vicinity of Elahera in Central Province, and the Tissamaharama region in Southern Province. This article describes the mining methods used in these major localities, the types of gemstone minerals found, and the inclusions observed within them.