Name: Diavik mine.
Location: The Diavik mine is located in Canada’s Northwest Territories, about 300 km north-east Yellowknife on the arctic barrenlands.
Holding and Controlling Company: Rio Tinto owns a 60% interest in, and operates, the Diavik diamond mine. Dominion Diamond Corporation owns 40% of the mine.
The mine is operated by Diavik Diamond Mines, a subsidiary of Rio Tinto.
Brief Description: The Diavik mine comprises the A21, A154 South, A154 North and A418 orebodies, with total mine life of 16 to 22 years.
All four kimberlite pipes are located in water under a large lake. Dikes have been built and maintained to hold back the water until mining has been completed, when the lake can be restored.
Brief History: Diavik was established following the discovery of four kimberlite pipes. In 1994, Aber Resources discovered diamonds in kimberlite pipes penetrating the granite beneath the bed of Lac de Gras.
By late 1997, drilling and tunnelling proved the diamonds to be sufficient in number and quality to recover.
Diavik began producing diamonds in January 2003, and the company sold its first rough diamonds in March that year. The mine has operated continuously since production began. The current mine plan is expected to take the mine’s production to 2024.
Geology/Mineralisation: The Diavik mine is located in Precambrian rocks of the Slave geological province. This ancient rock was formed about 2.7-billion to 2.5-billion years ago and is among the world's oldest geological structures. The Slave geological province is known to host deposits of gold, copper, zinc and diamonds, and has produced much of the north's mineral wealth.
The Diavik diamond pipes range in surface area from 0.9 ha to 1.6 ha and extend well below 400 m below the surface.
Reserves: Total proven and probable reserves as at December 31, 2015, were estimated at 19-million carats at 2.8 ct/t.
Mining Method: Openpit mining of the A154 South, A154 North and A418 pipes has been concluded and Diavik is mining these orebodies underground using sublevel retreat and blasthole stoping.
The openpits are no longer producing and no further excavation will be undertaken to alter the final wall slope configurations, but ongoing inspection, monitoring and analysis of the openpits by full-time technical staff are continuing to ensure the continuing integrity of the dikes, which now protect the underground operation.
Major Infrastructure and Equipment: The remoteness of the mine requires it to operate as a self-contained community, generating its own electricity and potable water, managing its waste that includes sewage and effluent treatment, maintaining emergency response and medical services, offering site-based recreation and education facilities, and providing meals and single-occupancy quarters.
All the mine workings, tailings impoundments, mine rock stockpiles, ore processing operations, shops and other service facilities, including dining and accommodations, are integrated at a one site.
Access to the Diavik mine is by air year-round and by a 425 km ice road that is constructed in winter every year and operational for only eight to ten weeks between January and March.
Prospects: The development of the A21 kimberlite pipe at Diavik is advancing as planned and will provide an important source of incremental production to maintain current volumes up to the end of the mines life. A21 is estimated to cost $350-million, with first production expected in 2018.
Contact Person: Investor relations executive David Ovington.
Tel +44 20 7781 2051