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Pics from topto bottom:Apparatusfordeterminingthe rateof oxygenuptakeduring goldleaching.Elutionthe MINIX TMgold-selectiveresin.The controlroom inMintek’sDC arcdemonstrationsmeltingfacility.will initially be used in development work on high-arsenic goldores, incorporating arsenic speciation and mass-balancing. Theequipment will eventually form part of a comprehensive facilityfor characterisation and problem-solving on gold leach andadsorption circuits, from both the process and the environmentalaspects.Process developmentAn extensive suite of testwork, including mineralogy,comminution and gravity concentration, leaching, adsorption,and carbon-in-pulp/carbon-in-leach (CIP/CIL) modelling, wasGold’s Modder East project. On the commercial plant, which isbeing designed by Bateman, about 40 per cent of the gold willbe extracted in a gravity circuit, with the remainder recovered byCIL. The work showed that recoveries of between 87 per cent andnew gold mine on the East Rand in almost 30 years, is scheduledto start production in the third quarter of 2009, and will reach a levelof 110 000 ounces (3.42 tons) a year at full output.Laboratory testwork was conducted to evaluate processing options aspart of the feasibility study, carried out by MDM Engineering, for ManoRiver Resources’ New Liberty gold project in Liberia. This project isproduction targeted for the latter part of 2007.A visit was paid to CVG Minerven in Venezuela to carry out a basicRecommendations were made regarding options for upgrading the plants’capacities and introducing new technology, as well as for tailings retreatmentand cyanide management. Further work, including testing of a bulksample for process development, is anticipated in 2007.The MINIX TM gold-selective resin was tested in a resin-in-leach (RIL) pilot plantat Fairview gold mine, which was run by Gold Fields in collaboration with thethen owners of the mine. Gold Fields, who supply the Biox® technology used atFairview, are continuing work with Mintek to reduce the thiocyanate concentrationin the tailings. The MINIX resin was also tested successfully for scavengingdissolved gold from slimes-dam return water at a Witwatersrand gold mine.A number of service projects were carried out for projects in Botswana, the DRC,Ghana, Mali, Romania, Zambia, and Zimbabwe, as well as South Africa. Ongoingtesting of surfactants (wetting agents) for application in heap leaching was conductedin collaboration with the manufacturer. A new CIP/CIL and resin-in-pulp/resin-in-leach(RIP/RIL) computer modelling programme was developed to interface with standardMicrosoft®Windows-based processes.PLATINUM-GROUP METALS (PGM) INDUSTRYDemonstration of the smelting step of the proposed ConRoast process for recoveringPGMs from high-chromium low-sulphur concentrates continued until the end of the yearunder review. Four major DC furnace campaigns have now been conducted, treating atotal of 28 000 tons of revert tailings and other materials with Cr 2O 3contents of up to 5per cent, at feed rates exceeding 1 000 tons per month. During the last campaign, whichran continuously for 17 months, the availability of the furnace was 91 per cent.The full ConRoast process involves the smelting of dead-roasted sulphide concentrates,with recovery of the PGMs and base metals into an iron-based alloy rather than a sulphideannual report 2007 20