Lunch, Eastern Pit and drill core at Mutanda, Katanga Province, DRC - Following the first pit visit, the group was shouted to lunch at the Mumi Club (upper left), overlooking Lake Nzilo, which was voted the best lunch of the tour.
After lunch they were transferred to the lookout over the Eastern Pit (lower image), for an introduction before driving down into the mine and walking to the face (central image) to study the high grade oxide ore. The day of the visit was a public holiday, and this pit was inactive, facilitating safe access.
After spending some time looking at the ore and hosts, the group next moved to the core yard to be led through a drill hole cutting the primary sulphide orebody and enclosing sequence (top right). The ore is hosted by bedded dolomitic rocks of the Kansuki Formation, which is generally regarded as the upper unit of the Dipeta Subgroup, which is in turn part of the Roan Group (e.g., Cailteux et al., 2007; Hitzman et al., 2012; Schuh et al., 2012). The immediate host sequence, as seen in drill core at Mutanda, is lithologically very similar to the host succession of the Mines Subgroup, as observed at Kolwezi and Tenke Fungurume, namely a structureless R.A.T.-like unit, overlain by banded to laminated dolomitic siltstones, a massive, silicified R.S.C.-like dolomite, and further banded to laminated siltstones, including intervals that are pyritic and carbonaceous. However, the sequence differs in that it also contains characteristic beds of jasper, hematite dusting and oolites, and regionally contains mafic volcaniclastic rocks, related to the mafic event in the immediately overlying Mwashya Subgroup. The right centre image is of very high grade, banded, bornite mineralisation within bedded dolomitic siltstones.
The core inspection was followed by an overview of the treatment plant, then our farewell and thanks to the Mutanda Mining staff for their excellent hospitality and a comprehensive and revealing visit. The group then left the mine for the drive back to Kolwezi, arriving just before sundown.
After changing and dinner, members of the group delivered presentations to the other participants on other sediment hosted copper deposits they have worked on, followed by discussion. Photographs by Mike Porter.
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