Miners unearthed from north-central Botswana a 1,111-carat diamond. According to Lucara Diamond, operator of the mine, the unadulterated gem, named Karowe Diamond after the mine where it was dug, measures 65 x 56 x 40 millimetres.

The Type-IIa stone is just smaller than a tennis ball, reports Bloomberg. In July, Lucara sold another Type-IIa diamond, which was 341.9 carats, for $20.6 million. But analysts said it is hard to estimate the value of the Karowe Diamond.

Edward Sterck, BMO Capital Markets analyst, explains in a note on Thursday, “It is almost impossible to estimate a value for such an extraordinary stone given that a valuation is highly dependent on the color, clarity and cutting and polishing characteristics.” Bloomberg writes that Lucara would likely sell it at a tender in Botswana, but it could take years before it is cut, polished and sold to a final owner.

It was the largest diamond found in the last 100 years since the Cullinan Diamond was discovered in a mine near Pretoria, South Africa in 1905, reports Gizmondo. Cullinan weighed 1.4 pounds and was thrice the value since it was 3,106 carats. It was cut into several large pieces, with two found in the British Crown Jewels.

Karowe is the second-largest gem quality diamond in the world recovered using Lucara’s newly installed Large Diamond Recovery XRT machines. The British Columbia-based miner focuses on mining the south lobe, which Lucara says is delivering value beyond expectations.

“This historic diamond recovery puts Lucara and the Karowe mine amongst a select number of truly exceptional diamond producers. The significance of the recovery of a gem quality diamond stone larger than 1,000 carats … cannot be overstated,” William Lamb, Lucara president and CEO, says in a statement.

Lucara owns 100 percent the Karowe Mine which is in production. It owns 75 percent of the Mothae Project in Lesotho, but the firm is divesting its share in the project.

Contact the writer at feedback@ibtimes.com.au or tell us what you think below