South Africa's mining output declined 15.9% in September compared to the previous year due to mine accidents and strikes, according to a report by Statistics South Africa.
The report said the primary reason for the decline was the fall in platinum group metal (PGM) production.
In September, PGMs, which include platinum, rhodium, palladium and iridium, declined 38.9% while diamonds and gold declined by 28.8% and 9.3% respectively.
Mined coal, however, increased by 4.4%.
Production at Impala Platinum, which generates 25% of the world's platinum, was curtailed in September due to a strike at Rustenburg mine.
South Africa, which holds the top position in platinum production, accounted for more than three-quarters of international platinum output in 2008.