Botswana, the world's largest diamond producer, has started to auction its own diamonds for the first time instead of selling them in Europe.
The auction is by the Okavango Diamond Company, which is government-owned.
Later in the year, De Beers, which co-owns Debswana, the main mining company with the government, will also move its sales to Gaborone.
Last year, De Beers moved its rough stone sorting operation, which had been based in London for nearly 80 years, to Botswana.
A BBC correspondent said about a dozen diamond buyers from around the world are in the capital, Gaborone, for the auction, which lasts for two weeks.
The government's long-term plan is to set up a diamond hub similar to Antwerp and Tel Aviv that will continue after the diamond mines close.
Botswana has long campaigned for its diamonds to be processed, sorted, marketed and sold from the country.
De Beers chief executive Philippe Mellier told the BBC that the diamond sales would turn Botswana into a major diamond hub, as it is already the biggest centre for diamond production.
"It's a global movement of big scale for the diamond business," he said.