Diamonds are mined at Williamson Diamond mines at Mwadui located 27km from Shinyanga town.
Formation of diamond
The diamonds at Mwadui are found in a Kimberlite rock which was formed in an intrusive rock of Magma which solidified in a Vent or pipe to form a volcanic plug. Later, this intrusion was exposed by erosion.
Mining of diamond
The opencast method is used because the mineral-bearing rock is found just below the surface of the earth. Heavy excavators scrape off the surface of the earth hence exposing the ore-bearing rocks. These rocks are then loaded onto waiting trucks and then taken to the factory where the rocks are crushed to small sizes.
Processing of diamond
- From the mining zone, the ore bearing rocks are taken by trucks to the crushing plant where the rocks are crushed to small sizes and then poured on a conveyor belt which transports it to the treatment plant.
- At the treatment plant, the ore is passed through separators. The diamond and some other heavy substances because of being dense, sink to the bottom while the remaining materials float as wastes.
- For further cleaning, the diamonds are further passed over belts covered with grease to which they stick. The wastes are removed electrically.
- The diamond is then cleaned to remove all the grease and its then ready for use e.g. making jewellery.
Factors favouring the development of diamond mining at Mwadui
- The diamonds are found near the earth surface hence cheap to exploit using open cast method.
- Diamonds at Mwadui are found in large deposits hence economic to mine.
- Mwadui diamonds are of high quality and on high demand on the international market.
- The landscape is generally flat hence easy to extract the minerals.
- Easy accessibility due to the presence of transport network by the railway and roads.
- Availability of adequate capital for investment provided by both the Williamson mining company and government.
- Nearness to agricultural land which provides foodstuffs to the workers.
- Availability of abundant skilled manpower both local and foreign expatriates to work in the mines.
- Presence of a variety of energy sources e.g. hydro electric power used in mining and processing minerals.
- Availability of modern technology used in the mining operations.
- Supportive government policy which encourages mining e.g. through investment and market research.
Importances of diamond mining at Mwadui
- The mine provides employment opportunities to many people hence improving their standards of living.
- It has led to the development of Mwadui town with accommodation, recreational and commercial facilities.
- The mining company constructed a dam which provides electricity to Shinyanga district.
- Facilitated development of infrastructures like roads, schools and hospitals which provide social services.
- The mining company trains its own labourers in mining related activities hence leading to skills acquisition.
- The mining company established reliable water supply to Mwadui town and neighbouring areas.
- Government earns revenue through taxes used for national development e.g. building roads.
- Through exports, government earns foreign exchange used for national development e.g. building hospitals.
- Facilitated development of industries which have led to economic diversification.
- Agriculture has been developed in the area due to demand from the miners.