Lucapa Diamond Co recently recovered a 227-carat Type IIa premium-quality stone from its Lulo mine in Angola with the help of Tomra’s X-ray transmission (XRT) sorting technology.

The diamond is not only the largest single stone to be recovered at the newly commissioned XRT large diamond recovery circuit at Lulo, but it is also Angola’s second largest recorded diamond. The Lulo diamond mine is a successful and long-running partnership between Lucapa (40% owner and operator), Endiama EP and Rosas & Petalas.

Stephen Wetherall, managing director at Lucapa, commented: “The recovery of the 227-carat diamond using the new XRT circuit justifies our investment in Tomra’s large diamond recovery technology, which has more than paid for itself with the recovery of this one stone alone. We had already seen what the implementation of this XRT technology delivered for Lucara in Botswana, enabling the recovery of the second largest diamond ever by the Karowe mine, Botswana, in November 2015.”

Geoffrey Madderson, segment manager, diamonds at Tomra Sorting Mining, added: “Tomra’s XRT diamond recovery technology has yielded another diamond of exceptional size and quality, and is proud to have delivered it to the Lucapa-operated Lulo mine in Angola. Tomra would like to congratulate and thank Lucapa and its Lulo partners for the good cooperation so far and the confidence shown in our technology.”

The Lulo large diamond recovery circuit, including a Tomra sorting unit, went into commercial operation in the December 2016 quarter, processing oversize alluvial gravels at the Lulo diamond project in Angola. As part of the new coarse recovery stream at the 150t/h diamond plant, the XRT technology has provided the Lulo partners with the capability to recover individual diamonds up to 1,100 carats. The XRT sorting technology is significantly more effective for the recovery of higher quality low-luminescing Type IIa diamonds.