LAS VEGAS–(BUSINESS WIRE)–Diamond prices were stable in August, which is traditionally a slower period for the trade. Upbeat activity at the Las Vegas shows reflected the robust US market that has been driving demand. Retail jewelers are having a strong year, spurring optimism across the supply chain. The RapNet Diamond Index (RAPI™) for 1-carat diamonds edged up 0.1% during August and has increased by 11.3% since the beginning of the year. RapNet Diamond Index (RAPI™) August YTDJan. 1 to Sep