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Ghana: Gold Mining Resurgence: Difference between revisions
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Ghana: Gold Mining Resurgence (view source)
Revision as of 12:03, 8 April 2015
, 12:03, 8 April 2015→Alteration of the physical environment
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''How artisanal miners extract gold'' | ''How artisanal miners extract gold'' | ||
''In a typical small-scale gold mining operation where hard rock is mined, the ore is excavated manually and size reduction is | ''In a typical small-scale gold mining operation where hard rock is mined, the ore is excavated manually and size reduction is | ||
carried out using a combination of jaw and rocker crushers, hammer, disc and stamp mills. The stamp mills and rockers are | |||
manually operated while the others are powered by diesel or electricity. Generally, the milled material is washed in a sluice | manually operated while the others are powered by diesel or electricity. Generally, the milled material is washed in a sluice | ||
lined with corduroy, jute material, miner’s moss or astro turf to obstruct the flow of slurry and concentrate gold particles. | lined with corduroy, jute material, miner’s moss or astro turf to obstruct the flow of slurry and concentrate gold particles. | ||
Alluvial ores do not go through comminution [the reduction of solid materials to smaller sizes] but are scrubbed, screened | Alluvial ores do not go through comminution [the reduction of solid materials to smaller sizes] but are scrubbed, screened | ||
and concentrated by sluicing. The concentrate in both cases is cleaned in pans and the gold is amalgamated with mercury. The | and concentrated by sluicing. The concentrate in both cases is cleaned in pans and the gold is amalgamated with mercury. The | ||
amalgam is then roasted to obtain the gold, which is sold to licensed buyer.'' <ref name="Nyame" />(p.133). | amalgam is then roasted to obtain the gold, which is sold to licensed buyer.''<ref name="Nyame" />(p.133). | ||
During the days GCD was the leading diamond miner in Ghana it created a 30-metre buffer zone alongside stream channels where mining was prohibited. This was a deliberate strategy to prevent environmental degradation and pollution. With the demise of GCD, artisanal miners felt free to begin mining these areas, leading to increased siltation of waterways, and to divert lengthy sections of stream channels. Such behaviour resulted in the complete diversion, for example, of the Birim River in the Akwatia area of Ghana, and in combination with deforestation and siltation also caused by small-scale miners, it has led to wholescale flooding during the annual rainy season, including loss of life and large-scale displacement of local peoples. | During the days GCD was the leading diamond miner in Ghana it created a 30-metre buffer zone alongside stream channels where mining was prohibited. This was a deliberate strategy to prevent environmental degradation and pollution. With the demise of GCD, artisanal miners felt free to begin mining these areas, leading to increased siltation of waterways, and to divert lengthy sections of stream channels. Such behaviour resulted in the complete diversion, for example, of the Birim River in the Akwatia area of Ghana, and in combination with deforestation and siltation also caused by small-scale miners, it has led to wholescale flooding during the annual rainy season, including loss of life and large-scale displacement of local peoples. | ||