GABORONE, Aug 1 (Reuters) – The sale of rough diamonds at Botswana’s Debswana Diamond Co fell 17% in the first six months of the year, data released by the central bank showed, amid a weak market underpinned by global macroeconomic uncertainty.

Debswana, a joint venture of Botswana and Anglo American Plc’s AAL.L unit De Beers, sells 75% of its output to De Beers with the balance taken up by state-owned Okavango Diamond Co.

Botswana and De Beers in late June agreed a new diamond sales deal in which the African country, the world’s No. 1 diamond producer by value, gradually increases the share of rough stones it gets from the joint venture over the next decade to 50%.

In the first half of the year, Debswana sold diamonds worth $2.179 billion from $2.622 billion in the same period last year, the Bank of Botswana said late on Monday.

In pula terms, the rough sales recorded an 8% fall to 28.621 billion pula, with central bank data showing the local currency depreciated 8.4% against the dollar in the 12 months to June.

Debswana, which produced 12.7 million carats in the first six months, accounts for almost all the diamonds produced in Botswana, with Lucara Diamond Corp’s LUC.TO Karowe mine being the only other operating diamond mine in the country.

(Reporting by Brian Benza, Editing by Bhargav Acharya and Bernadette Baum)