Botswana plans to conclude negotiations with De Beers on a diamond sales agreement by the end of April to replace the current 10-year deal that expires in January.     The government wants to see more gems cut and polished within the borders of the world’s second-biggest biggest diamond producer, creating jobs and boosting the state coffers, according to Lefoko Moagi, the minister of mineral resources, green technology and energy security.     An agreement is crucial for both parties. Botswana accounts for more than two-thirds of De Beers’ production, while the country relies on the gems for 90% of its exports and wants to derive as much benefit as possible from its mineral wealth.     Lefoko Moagi Photographer: Matthew Hill/Bloomberg “We are looking at April, not beyond, for all of this to happen and be successfully concluded,” Moagi said in an interview in his office in Gaborone, the capital. “We now want further to move into the value space; the bottom end of the business which involves your valuation, your pricing, cutting and polishing, marketing, selling, jewelry making.”