Royal Bafokeng Platinum (RBPlat) on Wednesday reported that the total tonnes delivered to concentrators for the three-month period ended September 30, had increased by 9.2% year-on-year to just over one-million tonnes and the total tonnes milled increased by 2.1%, also to just over one-million tonnes.
Year-to-date total tonnes delivered, and total tonnes milled amounted to 2.86-million tonnes and 2.87-million tonnes, respectively, representing increases of 16.4% and 14.4% year-on-year, respectively.
However, a disposal of concentrate agreement pipeline adjustment, accrued for the production months of May, June and July, was affected during the reporting period, which resulted in an artificial lowering of the built-up head grade by 1.8%.
At the miner’s Bafokeng Rasimone platinum mine (BRPM), in South Africa, total tonnes milled reduced by 5.1% to 580 000 t in the quarter and by 2.4% to 1.6-million tonnes for the year-to-date period.
Merensky tonnes milled for the quarter and year-to-date reduced by 91 000 t, or 18%, and 145 000 t, or 10.3%, respectively. The reduction in Merensky volumes was attributed to the combined impact of Merensky reserve depletion at South shaft and lower-than-expected operational performance at both the North and South shafts during the third quarter, RBPlat said.
Additionally, the quarterly operational performance was impacted on by increased geotechnical complexities associated with accessing and mining of “white areas” at the South shaft and localised geology encountered at the North shaft’s third phase.
Ramping up of the upper group two (UG2) production at RBPlat’s South shaft operation continued during the quarter in line with achieving the company’s stated output of 20 000 t a month by the fourth quarter, with 51 000 t of South shaft UG2 being milled for the quarter, amounting to 166 000 t, representing a 56.5% year-on-year increase.
For the year-to-date, UG2 tonnes milled increased by 32.4% to 425 000 t. UG2 volumes constituted 28.6% of total tonnes milled for the quarter and 25.1% for the year-to-date.
The built-up head grade for the year-to-date is just over 4 g/t of platinum, palladium, rhodium and gold (4E) metals compared with the grade of 4.1 g/t of 4E achieved in the comparative period in 2018, equating to a 3.4% reduction.
This reduction in head grade, RBPlat explained, was mainly attributable to the increase in lower-grade South shaft UG2 contribution, variability in ore mix and resource-area-dependent grade fluctuations.
Meanwhile, at Styldrift, the company said it was “encouraged” by the improvement achieved in key operating metrics during the third quarter and that it “remains confident that the strategies and action plans initiated to address operational challenges identified to date are delivering the intended results”.
This was done in support of reaching the 230 000 t a month milestone in the third quarter of 2020.
A total of 432 000 t of ore was delivered to the concentrators for the quarter, equating to a 21.3% increase against the comparative 2018 period, which represents a 16.8% improvement in tonnes a month delivered.
Tonnes milled for the quarter increased by 14.1% to 422 000 t, with year-to-date milled volumes increasing by 51.9% to almost 1.2-million tonnes.
“The built-up head grade at Styldrift continues to improve as the stoping tonnage contribution to overall tonnes delivered increases in line with the ramp-up profile,” the company stated.
The quarter-on-quarter and year-to-date built-up head grades improved by 8.9% to 3.6 g/t of 4E and 11.9% to 3.76 g/t of 4E, respectively.
Operationally, the focus remains on achieving improvements in operational efficiency through improved trackless mobile machine availability, minimising in-stope face to tip distances and artisan/operator upskilling programmes, RBPlat said.
In terms of concentrating, the total tonnes milled for the reporting period amounted to 1 002 t, representing a 2.1% increase compared with the corresponding 2018 period with increased mining volumes from Styldrift offsetting the lower BRPM volumes.
Merensky and UG2 tonnes milled were 837 000 t and 166 000 t respectively, with UG2 equating to 17% of total milled volumes.
The BRPM concentrator treated 719 000 t, of which 54 000 t was UG2 and the Maseve concentrator treated 284 000 t, of which 112 000 t was UG2.
The combined built-up head grade for the year to date remains unchanged at 3.91 g/t of 4E, compared with 2018.
The quarter-on-quarter built-up head grade reduced by 1.8% to 3.78 g/t of 4E as a result of changes in ore mix, specifically at BRPM owing to the increase in lower grade South shaft UG2 material and the negative ounce adjustment incurred during the quarter, RBPlat explained.
The lower recovery potential of the Maseve milling and flotation one circuit and variations in ore mix has impacted on overall recoveries, with recoveries reducing by 2.2% and 1.9% for the quarter and year-to-date respectively, compared to 2018.
The combined impact of the lower recoveries, 2.1% increase in milled volumes and a negative metal-in-concentrate adjustment accrued during the reporting period yielded a 1.8% and 2% quarter-on-quarter reduction in 4E and platinum metal in concentrate compared with 2018.
Platinum and 4E metal production amounted to 65 300 oz and 100 600 oz, respectively.
Year-to-date platinum and 4E metal-in-concentrate production increased by 12.4% and 12.2% year-on-year to 194 500 oz and 299 700 oz, respectively.
Further, total capital expenditure (capex) for the reporting period decreased by 60.1%, or R568.1-million, to R377.7-million as the company’s Styldrift project activity nears completion. Previously capitalised operating costs relating to the Styldrift project are now being expensed, the company added.
Replacement capex decreased by R10.8-million and R25.5-million for the quarter and year-to-date respectively when compared to 2018 in line with the completion of the North shaft Phase III Merensky project scope of work.