Lucapa Diamond Co. has been undertaking a kimberlite exploration program at its the Lulo diamond project in Angola designed to discover the primary hard-rock sources of the alluvial diamonds being mined along the Cacuilo River valley, which have achieved exceptional average run-of-mine sale prices of ~US$1,900 per carat. This morning they announced positive exploration results, recovering 45 diamonds of up to 3.75 carats recovered from stream bulk sampling. Preliminary analysis has classified several diamonds as top D-color. To date, alluvial recoveries in the valley have included 14 diamond weighing more than 100 carats, including Angola’s biggest recorded diamond weighing 404 carats.
The miner says that the latest kimberlite exploration phase is based on a detailed technical review of all previous exploration results, including airborne geophysical surveys and an extensive kimberlite drilling and mineral chemistry program, which defined more than 100 kimberlites within the Lulo concession. The Canguige catchment hosts five of 16 Lulo kimberlite pipes rated in a technical review as being most prospective to host diamonds. This is where Lucara has started is most recent round of drilling. The miner says the first stream bulk samples totalling 1,865 cubic metres (m3 ), produced highly-encouraging results. A total of 45 diamonds weighing 30.3 carats were recovered. This included eight diamonds weighing >1 carat and three diamonds >2 carats, the largest being 3.75 carats. The current sampling site located about 3km from Mining Block 46, which has produced Type IIa Specials of up to 88 carats, four +50 carat diamonds and fancy pinks and yellows.
“Across the history of diamond exploration, the recovery of diamonds and kimberlite indicator minerals from streams have been valuable pointers for the search of kimberlite pipes shedding those diamonds,” says Lucapa Managing Director Stephen Wetherall. “We are excited about the diamond recoveries from the Canguige stream bulk sampling and look forward to advancing the next phase of our kimberlite search within the Canguige catchment. We remain confident that the primary sources of the alluvial diamonds being recovered at Lulo await discovery and that our exploration efforts will be justified.” The Lulo kimberlite exploration licence is held by the Project Lulo joint venture (Lucapa 39% and operator; Endiama 51% and Rosas & Petalas 10%) and covers the entire 3,000km2 Lulo concession. The licence expires in April 2023. Lucapa is in discussions with the Angolan Ministry of Mineral Resources and Petroleum and Endiama to potentially secure a majority stake in the Project Lulo joint venture.
Photo: Lucapa Diamond Co., 31 carat Type IIa white diamond and fancy pink and yellow diamonds recovered from Mining Block 46