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Geology
The Kakanda and Kambove Copper-Cobalt deposits are hosted by sedimentary rocks of the Neo-Proterozoic Katanga System, situated within the Lufilian Arc. The Lufilian Arc and Zambesi Belt form part of a system of supracrustal Pan African belts of Neo-Proterozoic age in Africa and South America that are host to several important base metal provinces including the Central African Copperbelt which includes the Congolese (Katanga) and Zambian Copperbelts. The Lufilian Arc which contains both the Katanga and Zambian Copperbelts is one of the great metallogenic provinces of the world and contains some of the world's richest deposits of copper and cobalt.
The Cu-Co mineralization is almost entirely confined to the Mines Group of the Roan Series or Supergroup. Mineralisation does however occur at other stratigraphic levels, including within the Nguba and Kundelungu Series. In general the ore at Kakanda is contained in two layers, termed the upper and lower, which are separated by a barren or patchily mineralized siliceous dolomite which varies from massive to bedded and commonly stromatolitic, and contains some minor mineralized argillaceous horizons that are usually mined as internal waste.
The mineral deposits of the Kakanda Property include two distinct types:
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bedrock copper-cobalt orebodies that belong to the mineralization type Sediment-hosted Copper, Reduced-facies Subtype; and
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copper-cobalt bearing process plant tailings in valley dams.
Kakanda Tailings
The Kakanda tailings deposit comprise three separate zones including:
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Oxide-dolomitic tailings deposited in the western section of the tailings impoundment area prior to 1997 that were systematically drill tested and evaluated by IPRC in 1997,
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Oxide-silicate tailings deposited in the eastern section of the tailings impoundment area prior to 1997 that were systematically drill tested and evaluated by IPRC in 1997, and
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Possible cobalt rich tailings of unknown size and grade deposited upon the oxide-silicate tailings after 1997. Five samples of this material collected by MPH averaged 0.345% TCu and 0.466% TCo.
The Kakanda tailings deposit, excluding the post-1997 additions, contains leachable copper Indicated Mineral Resources totaling:
18.4 million tonnes averaging 1.22% TCu and 0.15% TCo.
MPH has reviewed the historic information on this resource and conducted a detailed audit of the grade/tonnage estimations. MPH concludes that the tailings material deposited prior to 1997 has been studied and evaluated to high standards by IPRC’s consultants and meet NI 43-101 standards for inclusion in an economic evaluation to feasibility study standards. These are the only resources on the Kakanda properties that currently meet such standards.
Since 1997 additional tailings have been and continue to be added to the Company’s Kakanda tailings deposit by a company that leases the Gecamines Kakanda concentrator. At this time there are no systematic investigations into the amounts and grades of new tailings in the deposit. From MPH’s site visit it is known that these new deposits cover most of the oxide silicate sector of the tailings dam, with unconfirmed reports that an additional approximately 2.0 million tonnes may have been added.
Kakanda North and South Pits
In the 1997 Bateman feasibility study it was determined that, of the two former producing areas allocated to IPRC, the North pit had the best potential for resuming production on a commercial basis.
In June 1997 SRK embarked on a mine planning study on the Kakanda North and South Pits hard rock resources. This was study was ultimately supposed to be the basis for the hardrock aspect of the Bateman bankable feasibility study. Due to the onset of war the study was not completed to such standards. Instead it remains a partially completed work that has utilized unsubstantiated Gecamines drilling information for a preliminary grade/tonnage estimation and pit modeling exercise.
Utilizing a 1% TCu cut-off grade, the provisional non-NI 43-101 compliant resources at the North Pit totaled 23.2 million tonnes averaging 2.62% TCu and 0.17% TCo, while the South Pit contained 8.7 million tonnes @ 2.21% TCu and 0.18% TCo. Preliminary optimum pits, based on average NPV as the prime indication, were determined at a cut-off grade of 0.98% TCu. Potential open-pit mineable mineralization after mining dilution and recovery for the Kakanda North Pit is 11.3 million tonnes @ 3.25% TCu and 0.20% TCo with a stripping ratio of approximately 8.8:1 while the South Pit has 2.6 million tonnes @ 2.25% TCu and 0.18% TCo with stripping ratio of 8.9:1. Due to the relatively low tonnage and high stripping ratio SRK decided to exclude the South pit from the planning exercise. MPH similarly concludes that due to the substantially higher tonnage at modestly better grade and stripping ratio, the North Pit area is the obviously higher priority prospect for ongoing investigations.
MPH is of the opinion that the hard rock mining aspect of the 1997 feasibility study should be updated to current standards.
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