Rio Tinto saw its diamond output fall in the third quarter of 2019 (three months ended September 30, 2019), citing lower carat grades from its Argyle mine in Australia and lower ore availability at the Diavik mine in Canada. The multinational mining group reported a 7% decline in diamonds produced during the quarter and a 9% drop over the first nine months of the year.
Rio Tinto produced a total of 4.55 million carats during Q3 2019, which is 7% fewer than the 4.90 mn cts produced during the same period a year earlier. For the first nine months of the year, diamond production reached 12.8 million carats, 9% fewer than the 14.1 million carats during the same period a year ago. At Argyle, carat ouput in the third quarter of 2019 was 3.56 million carats representing a 7% decline from the 3.83 million carats recovered in Q3 2018, but 8% more than the previous quarter. Rio Tinto said this was due to lower recovered grade, partially offset by stronger mining and processing rates. Over the first nine months of 2019, production at Argyle totaled 9.64 million carats (9M 2018: 10.86m cts).
At the Diavik mine in Canada, Rio Tinto’s share (60%) of carats recovered in the third quarter totaled 994,000 carats, which was also 7% lower than the 1.07 million carats recovered in the third quarter of 2018 and 16% lower than the previous quarter. The miner attributed it to lower ore availability from both the underground and the A21 open pit. For the first nine months of 2019, Rio Tinto’s share of carats recovered at Diavik was 3.19 million carats, slightly below the 3.28 miilion carats recovered during the same period in 2018. Rio Tinto is the majority (60/40) partner in the Diavik mine with Dominion Diamond Mines holding the remaining share.
Rio Tinao has maintained its diamond production guidance for 2019 between 15 and 17 million carats, compared with 18.4 million carats recovered last year.