Midnight Sun Mining Corp (TSX-V:MMA, OTCQB:MDNGF) said Wednesday that its first drill holes at the Dumbwa target in Zambia have confirmed a copper system running along a 20-kilometre stretch of prospective ground.
The Vancouver-based company reported intercepts including 0.51% copper across 39.7 metres, with a higher-grade zone of 1.13% copper over 7 metres. A second hole cut 0.48% copper across 25.9 metres.
These results come from holes DBW-25-003 and DBW-25-007, drilled 500 metres apart, with both showing copper sulphides concentrated in vertical shear zones.
Copper grades are expressed as a percentage of metal content within a rock sample. While the numbers may sound small, 1% copper over long intervals is considered significant in the mining industry, especially if it is near surface and in rocks that can be processed at low cost.
Kevin Bonel, chief operating officer, said in the release: “We have successful initial intercepts confirming sulphide copper mineralization at Dumbwa, just a few holes into the first systematic drilling program ever conducted on this massive target.
"We do not believe we have reached the heart of the system yet, and as we advance along this immense strike extent, we expect to see areas of both broader mineralization and increased grade.”
The company compared early drilling at Dumbwa to work Bonel had previously been involved in at Lumwana, a large Zambian copper deposit now in production. “Holes DBW-25-003 and DBW-25-007 have provided grades and thicknesses which are comparable to those encountered at Lumwana, reinforcing our analogue between the two, very early on in this process,” he said.
Two step-out holes, drilled east and west of DBW-25-007, confirmed that multiple shear zones host copper and that the system remains open in several directions. Samples from those holes have been sent for analysis at SGS Labs in Kalulushi, Zambia.
Midnight Sun is exploring its Solwezi project in Zambia’s Copperbelt, which lies beside Kansanshi, Africa’s largest copper mine, operated by First Quantum Minerals. The company said it is continuing to drill at Dumbwa while waiting for further assay results.