(IDEX Online) - A huge 21.01-carat diamond has sold online for $2.5m, setting a new world record.The D / IF gem, set in a platinum engagement ring, was bought by a 59-year-old businessman after viewing it online.He had it delivered by an armed security to an hotel in Montana, USA, and promptly proposed to his partner. She accepted.Don Palmieri, founder and president of GCAL (Gem Certification & Assurance Lab), in New York, which appraised the diamond, said: "I believe it might have sold for nearly $1 million more at a high-end jeweler. "This is an enormous sale that would normally take place in person." The record for an online diamond sale was held previously by a 28.86-carat D / VVS1 stone, which sold for $2.1m in a Christie's Jewels Online sale in June 2020.Pic courtesy GCAL.