JOHANNESBURG - South Africa’s rand was weaker on Thursday after disappointing mining data and as struggling state power firm Eskom started controlled electricity outages because of a wage dispute with labour unions.

At 1635 GMT, the rand traded at 13.3700 per dollar, 0.5 percent weaker and not far from a six-month low of 13.4400 struck on Wednesday.

South African assets have been hurt recently by weak economic figures and an unfavourable external backdrop which has seen global investors pull back from emerging markets.

Data showing that mining output fell 4.3 percent in April came after April retail sales undershot expectations and first-quarter gross domestic product contracted by 2.2 percent.

Those data points have added to evidence that the economy is yet to pick up momentum following Cyril Ramaphosa’s takeover of the presidency in February.

Ramaphosa has courted investors with promises to woo investment and root out corruption, but he faces an uphill battle to get the economy firing on all cylinders after a decade of stagnation under his predecessor, Jacob Zuma.

That task became harder on Thursday, when Eskom — which produces more than 90 percent of the country’s power — started controlled outages as protesting union members disrupted coal supplies and blocked some staff from going to work.

Labour unions have threatened a total shutdown of Eskom’s operations unless it meets their demands for a 15 percent increase in salaries.

The last time Eskom had to resort to controlled power outages in 2015, economic output was affected.

Stocks were mixed on Thursday, with bourse heavyweight Naspers under pressure while banks were in demand.

The JSE Top-40 index edged down 0.04 percent to 52,178 points, while the broader All-share index inched up 0.1 percent to 58,495 points.