The inferred mineral resource at December 31, 2017, was 3.36 million ounces of gold (including refractory) at 3.93g/t, increased primarily through exploration at the Wassa underground gold mine in western Ghana. This compared with the 3.13Moz at 4.77g/t at the end of 2016.

Measured and indicated mineral resources were largely unchanged on the year at 4.4Moz of gold, while proven and probable mineral reserves were at 1.7Moz of gold, down from 1.9Moz at the end of 2016.  

Golden Star said it expected to release another estimate update to the inferred mineral resource during the June quarter, which would incorporate all 2017 drilling at Wassa, including the nine drill results previously reported and an additional two holes drilled subsequently.

Golden Star CEO Sam Coetzer said the focus this year was on growth through exploration and continued operational delivery. 

"Our exploration programme has the primary objective of gaining a stronger understanding of the Wassa deposit at depth, which remains open downplunge," he said.

The second objective, according to Coetzer, was to expand the high-grade mineral resources at the Prestea underground gold mine in south-western Ghana and to assess the potential of five new targets to supply high-margin ore to its two processing plants.

Golden Star earlier in the year announced commercial production had restarted at Prestea, 15 years after the mine previously operated.