Sales of rough diamonds by Okavango Diamond Company (ODC), the state owned company that conducts tender sales for 14% of the production of Debswana, have declined by 20% in volume terms over the first five months of 2015 as compared to the same period a year ago the company said, according to a reports in the media.

ODC sold 1.02 million carats worth $193 million during the four tenders it has conducted so far during the year, the reports stated, adding that the decline was a result of weaker market conditions.

ODC Stakeholder relations executive Kutlo Thathana said, “Global rough prices have softened since the 4th quarter of 2014, largely as a result of weaker polished prices.”

An agreement signed with De Beers in 2011 ensures that supply to ODC from Debswana increases by one per cent annually, until it reaches 15% by 2016. Last year the company sold approximately 3.27 million carats, achieving revenue of $552m.

While the company only sells through auctions at present, it may consider selling some portion of its diamonds to fixed clients through contract sales in the future.