The latest mining production report released Thursday showed May was the third consecutive month of year-on-year decreases, although the rate of falls had slowed from a 8.5% drop in March and 4.4% fall in April.
According to Stats SA, manganese ore output in the country dropped 23% on the year, while gold production dropped 16.2%. Production of PGMs fell 9.6% from May 2017 and coal dropped 4.2%.
Despite the year-on-year decrease, seasonally adjusted mining production in May rose 5% from April.
Looking at seasonally adjusted output over the three-month period ending May, Stats SA noted that there had been a fall of 2.6% from the previous three-month period, with negative growth rates in 12 mineral groups and minerals.
The largest negative contributor was iron ore with 1.6 perentage points, while PGMs were the largest positive contributor at 1.3 percentage points.
Stats SA also looked at mineral sales for May, which rose 15.1% year-on-year, with manganese ore the main positive contributor, up 94.2%.
Coal sales rose 16.5% on the year, the volume of PGMs sold increased 13.5%, gold sales jumped 11.2% and iron ore sales were up 19.9%.
According to the report, seasonally adjusted mineral sales at current prices increased by 5.2% month-on-month in May 2018.
In the three months ended May, Stats SA found that the seasonally adjusted value of mineral sales at current prices fell 0.8% from the December 2017-February 2018 period.