GLOBAL mining giant Rio Tinto plc says diamond production at its Zimbabwean producer Murowa Diamonds (Murowa) has slumped 34% from the last quarter in 2013 to 69 000 carats in the first quarter of 2014, due to lower grades.
In a statement, Rio Tinto said output was 12% lower than the first quarter of 2013, “with slightly lower ore processed and the impact of wet weather on mining operations, which were partially offset by processing previously stockpiled material”.
In 2013, Murowa produced a total of 322 000 carats of diamonds, out of combined 16,03 million carats produced by Rio Tinto-including output from the group’s Argyle Mine in Australia and Diavik mine in Canada which produced 11,4 and 3,3 million carats in the year under review, respectively.
Rio Tinto owns 100% of Argyle and 60% of Diavik.
At Argyle, carats recovered were 24 % higher than the first quarter of 2013, reflecting higher grade ore from the underground mine and the processing of highly concentrated tailings.
Argyle production in the first quarter of 2014 was 22% lower than in the fourth quarter last year due to the exhaustion of all remaining open pit stockpiles in the fourth quarter and significant wet weather experienced in January and February which temporarily impacted mining and processing operations.
Diavik had a strong operational performance in the first quarter with a 17 % increase in ore processed.
Carats recovered were 4% lower than the first quarter of 2013 due to a greater proportion of mined and processed ore coming from a lower grade pipe in the period under review.
In June last year, Rio Tinto said it was reversing its initial decision to dispose of its diamond operations after the market failed to meet its asking price.
The move disappointed seven potential suitors who had been linked to the takeover of part of or the entire Rio Tinto stake in Murowa.
Murowa’s operation is located near Zvishavane in South Central Zimbabwe and is owned 78% by Rio Tinto plc while the remaining stake is owned by Riozim Ltd, an independent Zimbabwean owned listed company.
The company said three kimberlite pipes were discovered on the mine site in 1997.
“The resource has the potential to be expanded to 6-7 times its current production level. A review of the feasibility study for this expansion is currently underway, as are discussions with the Zimbabwean government on the required investment environment to support a project of this magnitude,” said the company.