Argyle Boosts Rio Tinto Diamond Output

RAPAPORT... Diamond production at Rio Tinto rose 11% year on year to 4.6million carats in the first quarter of 2018, driven by an increase in outputfrom its Argyle mine. The Australia-based operation yielded nearly 3.6 million caratsin the first three months ending March 31, an 18% jump over the same periodlast year. The growth was due to the processing of higher-grade alluvialtailings, the company said last week. The increase came despite plans to scale down operations atArgyle, after Rio Tinto last month reduced the mine's ore reserve estimate by45% - enough to continue operations until 2020. The surge at Argyle offset a 6% drop to almost 1.1 millioncarats at the Diavik mine in Canada, in which Rio Tinto owns a 60% stake, with theremainder held by Dominion Diamond Mines. The decrease was caused by the lower gradeof ore recovered. Rio Tinto is working on a new project at Diavik, the A21, afourth pipe located just south of the mine's existing operations, which it saidwould ensure the continuation of current output levels. The company anticipatesthe A21 project to be at full production capacity during the fourth quarter. The miner expects to produce 17 million to 20 million caratsfor the year compared to 21.6 million carats last year.