A 24.21 ct rough diamond on a scanner at Alrosa’s selling organisation in Russia, where the sorting, valuation and sale of Alrosa diamonds are carried out. The United Selling Organisation employs 500 professionals who grade the gemstones, with diamond acceptance tracked on a computer database. Russia has expanded its footprint in Africa by returning to Zimbabwe, where Alrosa mining engineers and geologists are active. Alrosa is the world’s biggest diamond miner by volume.