Lucara Diamond Corp. has recovered a 692.3-carat diamond from its Karowe mine in Botswana, the second massive rough from the deposit this month. The white, type IIa stone came from the EM/PK(S) unit in the south lobe, known for its large, high-quality rough, Lucara said on Monday 21st of August. The miner found the diamond via its XRT unit, which uses X-ray technology to identify huge stones in large pieces of ore before they get broken up.