RAPAPORT... Petra Diamonds has sold three exploration projects to Botswana Diamonds for $300,000, the mining companies announced Monday.The transaction includes Petra's KX36 project, a kimberlite in Botswana the miner discovered in 2010, as well as two other prospecting licenses in the country, and a bulk-sampling plant. Botswana Diamonds will acquire the assets by buying holding company Sekaka Diamonds Exploration.In addition to the $300,000 sale price, Botswana Diamonds will grant Petra a 5% royalty on future diamond revenues should any of the operations reach production.The disposal helps Petra focus on improving efficiency at its core mines while keeping the opportunity to profit from future production, said Petra CEO Richard Duffy. The transaction is unrelated to Petra's plans to sell its entire business, including its mines, which it announced last month.Image: Rough diamonds. (Shutterstock)