The company said underground grade was 7 per cent higher, with the majority of the firm’s operations producing higher kilograms and generating net free operational cash flow.
With a 7 per cent increase in the average Rand/kg gold price revenue increased by 10 per cent to US$321 million during the quarter.
Chief executive officer Peter Steenkamp said the higher productions strengthened the firm’s cash flow allowing them to repay their debts and to fund Golpu.
The company said the production results resulted in Harmony recording headline earnings of US$5 million.
The capital cost to build Stage One of the Golpu project in Morobe is estimated at US$2.3 billion with production expected to commence in 2020.
Harmony has a 50 per cent interest in the project.