Rio Tinto Group (RIO) is making another move to reduce its coal exposure, announcing Wednesday the sale of its Mount Pleasant project to Indonesia's Salim Group for $224 million. Salim, controlled by Indonesian billionaire Anthoni Salim, will buy the mine through Australian unit Mach Energy Australia Pty Ltd. In addition to an upfront payment, the agreement includes possible royalty payments should coal prices rebound from their recent slump to seven-year lows. London- and Melbourne-headquartered Rio Tinto has been looking for buyers for its New South Wales coal assets for more than a year as it seeks to reduce its exposure to the commodity, which is suffering a global supply glut and declining demand as power stations turn to cleaner-burning natural gas. Rio sold a 40 percent stake in its Bengalla mine to New Hope Corp. for $606 million in September.