Bikita

Bikita

BIKITA (EN: Bikita; RU: Бикита) is the deposit of the rare-metallic pegmatites within Zimbabwe, one of the largest ones within the world in terms of the reserves of lithium, cesium, beryllium, and tantalum. It has been discovered during the 1911. It is confined to amphibolites and crystalline schists of the Precambrian. The pegmatitic field is of the length of 3 kilometres, and of the width of 150-180 metres. The major reserves of the rare-metallic ores are concentrated within the slightly dipping pegmatitic field of the tabular form with the length of 1.8 kilometres, and with the thickness of 28-62 metres. The ore body has the clearly expressed zonation, and is submerged with slight inclination into the south-east direction (Figure).

The pegmatites are of the quartz-albite-muscovite composition, with association of lithium, cesium, beryllium, and tantalum minerals. The lithium minerals are represented by lepidolite and petalite, and also by spodumene, amblygonite, bikitaite, and eucryptite, the cesium minerals are represented by pollucite, the beryllium minerals are represented by beryl, the tantalum minerals are represenetd by tantalite, microlite, and simpsonite.

The total reserves of the ores are: 4.6 million tonnes of the lithium ones (2.6 million tonnes of the petalite variety, with 4.13% of the Li2O content, and 2 million tonnes of spodumene and lepidolite variety, with 1.7% of the Li2O content); 222 thousand tonnes of the beryllium ones (12 thousand tonnes with 1.0% of the BeO content, and 210 thousand tonnes with 0.1-1.0% of the BeO content). The reserves of pollucite are 100-150 thousand tonnes with 24% of the Cs2O content, the reserves of the tantalum pentoxide are 5.0-7.0 thousand tonnes. The deposit is being developed by the open pit method.

Earlier than the 1950, there were operated the cassiterite placer deposits, from which there have been extracted 200 tonnes of cassiterite, from which there have been extracted 100 tonnes of tantalite. Since the 1952, the deposit is being developed by the "Bikita Minerals Ltd." company. The complex ores of the major body are worked by the open pit mines at the depth of up to 40 metres. The productive capacity of enterprises is 40 thousand tonnes of petalite per year (1980). There are subjected to beneficiation the poor quartz-lepidolite ores (2.3 thousand tonnes of concentrate per year).