In Tanzania, diamonds are still in abundance. It is said that deposits of the most sought-after rare metal at the Williamson mine at Mwadui can go on for more than 50 years. Presently, the mine plan has been “alive” for 18 years while the potential life span is estimated to be of an additional 50 years plus.
The current mine plan is to ramp up run-of-mine (ROM) production from 2013 to 2016 following the introduction of a re-crush system into the plant circuit. Already the mine output increased significant major rehabilitation to its treatment plant. From July 2012 to March this year diamond production increased by 471%. The production has gone up from 21,570 carats in 9 months that ended in March 2012 to 123,243 recorded in 9 months that ended in March this year.
Williamson mine produces 5.6 carats per hundred tonnes (cpht), which remains in line with guidance of 5.5 cpht backed by commissioning of the reconstructed treatment plant. The mine that experienced extensive development to increase its capacity last year saw its treated tonnage increased by 436 per cent from 423,131tonnes to 2,266,113 tonnes in the said nine-months. The Mwadui mine progression came about as good news but before this many people believed that deposits at the mine had been completed.
The swelling production only came from phase one of development. The mine’s Phase 2 development project, which was initially planned to take the mine to 10 million tonnes yearly (mtpa), is now pending, though the firm remains considering methods to further significantly increase production beyond 3.6mtpa. Depending on appropriate electricity and water supply, an expansion plan above this level will be dependent upon those variables, as well as the results recorded from treatment of the rebuilt plant of main pit material over the medium term. According to Wikipedia, Williamson is the world’s largest economic kimberlite by surface area amounting to 146 hectares in size.
A brief background to the Williamson mine:
It is a historic source of high value Type II diamonds and impressive pinks. It is Tanzania’s only significant diamond producer and in spite of having been operated continuously since 1940, the pit is only 90 metres at its deepest point due to the huge deposit size.
1940 was the year that the mine was discovered by Dr John Williamson, a Canadian Geologist and is the largest economic primary diamond deposit to be in continuous production. By the 1950s the mine had advanced into a successful operation with high-tech equipment and a labour force of some thousand.
In 1958, the mine was sold to an equal partnership between De Beers and the colonial Government of Tanganyika. De Beers operated the mine until 1973. From 1974 to 1993, the mine was operated by STAMICO – the State Mining Corporation. In 1993 De Beers returned to Williamson as operators, together with a recapitalisation and ownership restructuring. Production amplified to roughly 195,000 yearly to 2005.
Petra Diamonds is an independent diamond mining group and an increasingly important supplier of rough diamonds to the international market. The corporation has welfares in 8 producing mines: Seven in South Africa (Finsch, Cullinan, Koffiefontein, Kimberley Underground, Helam, Sedibeng and Star) and one in Tanzania (Williamson).
At least life will continue at Mwadui mine, as diamonds seem to be abundant.