Production dropped 16.2 per cent from a year earlier, compared with a revised 5.8 per cent contraction in April.
Gold output in South Africa, once the world’s biggest producer of the metal, declined the most since February 2017 in May.
Pretoria-based Statistics South Africa said that gold production has been down for the last eight months.
Total mining output shrank for a third month, dropping 2.6 per cent from a year earlier compared with a revised 4.4 per cent retreat in April, it said. Production of platinum-group metals, of which South Africa has the largest known reserves, increased for the first time in six months, expanding 9.6 per cent from a revised 6.3 per cent contraction a month earlier.
Ageing infrastructure, reserve depletion as well as accidents have raised costs and curbed mines’ output in South Africa. Mining companies came under added pressure late last year and in the start of 2018 from the stronger rand and have responded by closing shafts and cutting thousands of jobs in a labour-intensive industry.