Berkeley Mineral Resources, the UK-listed junior primarily engaged in processing mining tailings, has announced a decision to sell the washplant tailings from the Kabwe lead/zinc mine in Zambia without further processing. The Kabwe mine was discovered during 1902 and commenced operations in 1904, reaching full-scale production in 1906. It officially closed down on 3 June 1994 due to its operations becoming uneconomic at that time. The site was placed under care and maintenance by the national mining company The Zambian Consolidated Copper Mines (ZCCM). Berkeley owns the rights of all the stockpiles of tailings at the Kabwe mine complex.
The washplant slimes dumps include residue historically produced at Kabwe prior to its closure through the washing of concentrates. Because of the high combined grade of lead and zinc at 17.83%, this section of tailings is believed to be readily saleable without further processing. Subsequent testing has revealed additional minor traces of copper, vanadium, iron and manganese. Following consultation with mining advisory firms, the Board have concluded that the value of the JORC-compliant dry tonnage of 503,189 would be maximised by the sale of the material without further processing. The Directors considered that the investment required to process these tailings and concluded a dedicated washplant flotation plant to produce concentrates would not be the best use of capital at this stage of the company’s development. The directors believe that the Kabwe site is ideally located for rail transport through Indian Ocean ports to smelters in Far Eastern markets and the washplant sections of the stockpiles are adjacent to the Kabwe railway sidings.
As a result of the decision to sell the washplant tailings without further processing the leach plant pre-feasibility study, currently being undertaken by Metanza, will focus on the main leach plant and slag stockpiles. The leach plant study will include design criteria, major equipment listing, and capital and operating cost estimates for the recommended processing routes. Further drilling of the slag stockpiles will be undertaken to complete the resource information for the study. Mintek is currently completing mineralogy and metallurgical testing of composite samples of these stockpiles concurrently with Metanza’s work. Masoud Alikhani, Chairman, commented: “I am pleased we have now been able to make this decision, based on commercial criteria. The near-term sale of the washplant tailings will bring us substantial regular cash-flow and help speed the pre-feasibility study work. Once this is complete we will then be in a position to start processing the main leachplant stockpiles as soon as possible. We are proceeding with maximising the potential of Kabwe while at the same time reviewing several other tailings deposits within Zambia.” In addition to its activities at Kabwe, Berkeley has signed a Memorandum of Understanding with Ng’wena Mining Resources under which it could acquire 76% of the copper tailings from the former Roan Antelope mine at Luanshya, 145 km north of Kabwe.
