An affordable solution for micro miners

Simple and affordable pieces of equipment to concentrate gold were developed by the Colleges and Institutes Canada (CICAN) Project in Colombia using locally available materials found in junk yards and metal shops. A chain mill, shaking table and flotation cell were built in Colombia and demonstrated to micro-miners, who typically process less than 2 tonnes per day (tpd) of ore. An economic feasibility study was conducted for four different ore processing rates (0.2, 0.5, 1 and 2 tpd) and different levels of gold recovery that were compared with the current practice of taking ores to processing centers (entables), where the whole ore is typically amalgamated in small ball mills called cocos. For the processing rates of 0.2, 0.5 and 1 tpd, it was determined that the miners must sell their concentrates to cyanidation plants at 65% of the gold content. At 2 tpd, miners could further leach the concentrates with cyanide using a mill-leaching technique. Although the results show that the CICAN approach is profitable at all levels of production, gold recovery must be higher than what is normally achieved at the entables using amalgamation (~30%). For miners processing 0.5 tpd or less of ore, their recover.