Bogala

BOGALA (RU: Богала) is the deposit of graphite at the south-west of Sri Lanka. It is confined to the Highland series of the Archean gneisses (biotite-hornblende, garnet, pyroxene) and crystalline schists. The depositions of graphite are represented by the veins and lenses, sometimes by the nests among the graphitized gneisses. There prevail the veins with the thickness of 0.6-1 metres, with the length of up to several tens of metres. The content of graphite within the ores ranges from 40-60% to 85-90%.

Near the graphite veins, there are developed the disjunctive dislocations, to which there are confined the zones of crushing with the thickness of up to 2 metres. The main mineral is graphite. In the form of the impurities within the veins, there may be found the milky-white quartz, and also calcite, pyrite, less often chalcopyrite. The explored reserves of graphite are 52 thousand tonnes (1976). The deposit is being developed by the 2 underground mines, which are situated at the distance of 150 metres one from another. The ore, which has been extracted, after the manual sorting, is beneficiated at the flotation factories within the Colombo and Bogala cities. During the 1977, there have been extracted 5256 tonnes of graphite. The produce is exported into the 19 countries. The major export of graphite (60%) is accounted for Japan, the USA, and the Great Britain.