Platinum producer Lonmin said production fell in the first quarter as a lull in December and the impact of annual stocktaking weighed.
The company also said that two fatalities, which occurred on 5 December, and the end of fourth quarter 2018, had impacted output.
'The loss of our colleague is deeply regretted and we extend our deepest condolences to his family and friends,' the company said.
Mining production fell 7% to 2.2m tonnes in the first quarter from a year ago, with platinum sales 4.6% lower and precious metal sales 12.7% lower at 140,488 ounces and 255,152 ounces, respectively, compared with last year.
Total cost of production increase to 6.4% to R3.9bn and unit costs increased 16.5% to R14,795 per PGM ounce.
The US Dollar basket price of $1,076 an ounce was up 11.2% from a year earlier, while the corresponding Rand basket price of R15,389 per ounce was up 17.0%.
Sales guidance for the full year was maintained at between 640,000 and 670,000 platinum ounces. Unit cost guidance was left unchanged in a range of R12,900 to R13,400 per PGM ounce produced, as was capital expenditure guidance of between R1.4bn and R1.5bn.
'I am encouraged by the increase in the PGM basket price driven by Palladium and Rhodium. Going forward into the second quarter, the Lonmin team continues to focus on safe mining production,' said Ben Magara, Chief Executive Officer.
At 8:38am: (LON:LMI) Lonmin PLC share price was -0.72p at 60.53p