Diamond expected to fetch at least US$70M at London auction

Canadian mining company Lucara is putting up its uncut, 1,109-carat diamond called the "Lesedi La Rona" for auction on Wednesday at Sotheby's in London.

The gem is the largest uncut diamond in the world, and the second largest ever found. It is expected to sell for at least US$70 million.

The tennis-ball sized diamond is overshadowed only by the 3,106.75-carat "Cullinan Diamond," which was found in South Africa in 1905.

The Lesedi La Rona's massive size made it impossible to fit into the scanners used to price precious stones.

However, a 813-carat diamond, called the "The Constellation," found in the same mine in Botswana, was sold by Lucara at auction for $63 million last month.

The auction is set to be held at Sotheby's at 6 p.m. local time.