REVIEW OF OPERATIONS
The year 2005 is regarded as a transition year as stacking on the heaps slow and construction commences on the new plant installation
Operations
Guinor has operated a number of relatively shallow open pits through SMD in the Lero-Fayalala (LEFA) Corridor, a 10 km long zone within its Dinguiraye concession in Guinea, West Africa. The pits currently produce oxidised material consisting of surface laterites and colloidal saprolite ore below. In the LEFA Corridor the depth of this oxidised material varies between 35 and 80 metres. When the present economic mineable oxidised ore is exhausted the pits will be maintained while awaiting expansion that will entail the exploitation of the underlying primary ores. Mining is done by a contractor who employs a fleet of two O&K RH40 hydraulic excavators and thirteen Caterpillar 773D dump trucks, backed up by auxiliary equipment such as dozers, graders, water trucks and front-end loaders. Heap leaching is used to extract the gold from the saprolite ore which is crushed and blended with cement before being agglomerated into pellets. It is then transported by a conveyor system to the leach pads.
These stacked pads are then irrigated with a low grade cyanide solution and approximately 90 per cent of the gold is recovered over a period of around 90 days. The pregnant solution containing gold is pumped to closed tanks with activated carbon. The gold attaches to the carbon and is subsequently stripped using a high pressure technique to form a concentrated gold solution. It is then deposited on steel wool cathodes by electrowinning and the gold loaded cathodes are smelted to form gold bars which are called dore of approximately 93 per cent purity. Finally the dore bars are shipped to a commercial refinery where 99.99 per cent pure fine gold is produced.
Production 2004
During 2004 ore production came from the Fayalala and Tambico deposits. In the last quarter of the year waste stripping commenced in the preparation of the expansion of the Lero pit. A total of 1.27 million tonnes was moved during 2004 at a grade of 1.97 g/t of gold. Some 838,000 tonnes of marginal ore has been stockpiled separately and it is expected that this low grade material will, in the future, be of economic value for the potential CIL plant. A record crusher throughput of 1.04 million tonnes was achieved and placed on the heap leach pads at an average grade of 2.28 g/t. In addition 233,000 tonnes of ore at 1.11 g/t was placed on the dump leach pads. The gold production for the year amounted to 77,245 ounces and at the end of the year the run of mine stockpile contained just over 200,000 tonnes of ore.
Production Targets for 2005
The year 2005 is regarded as a transition year as stacking on the heaps slow and construction commences on the new plant installation. Production has been planned to focus on the objective of preserving as much of the mine reserves as possible for the more profitable new project, whilst maintaining a neutral cash flow until the expansion is commissioned. Production levels will be reviewed throughout the year depending on the prevailing spot gold price. Output during 2005 will centre on the Fayalala pit with cut backs on the ore from the Lero pit. Only an estimated 400,000 tonnes of ore is budgeted to be mined for the heap leach pads in 2005. The leach facility is again expected to place over a million tonnes on the pads, with mined output being supplemented by material from the low grade stockpiles. Gold production for the year is forecast at approximately 50,000 ounces.
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