Kategorien: Bergbau {Technik}


After a long decline of gold production in Ghana since 1986 the gold mining sector is recovering and mainly foreign investment led to substantial exploration efforts as well as to the opening up of new mines and/or rehabilitation and expansion of the existing mines after their divestiture (privatization). Foreign junior exploration and mining companies and established international mining houses are currently exploring the country in search of large, therefore commonly low-grade gold deposits which are amenable to highly mechanized open pit mining. Beside such orebodies of the disseminated type or in granites, Ghana is endowed with many occurrences of gold quartz veins and banket reefs, which vary in width from a few centimetres to several metres and have striking length from a few 10 meter to several kilometer. Whilst such larger orebodies with ore reserves of above 1 Mio. tons are a target for industrial mining operations, the smaller "stringer"-occurrences are not of interest, if not only as indicators in prospection for possible adjacent disseminated mineralization. Such restricted orebodies could offer investment and employment opportunities for Ghanaian owned mining groups and companies and should therefore contribute also to economic development of the hinterland. Some of these orebodies as well as the ubiquitous gold bearing alluvials are currently mined by artisanal small scale miners, commonly called "galamsey", which use manual labour only and employ simple handtools in their operations. A visit to such operations will convince any observer that in almost all cases the operations are either inefficient, including the skimming of orebodies, or dangerous, or environmentally unsound or a combination of these. This is due to the long oppression of small scale mining activities first by the Colonial Government from about 1920 ongoing, later by the Ghanaian authorities after Independence. Only in 1986 under the Minerals and Mining Law, PNDC-Law 153 was the small miner legally recognized and a basis laid for his operations. Vast experience in narrow vein mining, which was available among African small scale miners before and around the advent of this century has been lost. To prove this point, mention should be made of the African engineer T.B.F. Sam, who managed and operated singlehandedly the Adja Bippo Mine near Tarkwa before 1900, the only mine of all the mines in operation since 1880 which was profitable and declared dividends (Rosenblum, 1974). Today it can still be assumed that there will be no re-juvenation of skilfull vein mining by African small scale miners as long as it has not been proved to Ghanaian investors that such operations could be viable. The proof can be presented best by a few reference operations applying durable, locally available machinery, simple and sound mining and extraction methods, basic safety standards and bearable working conditions as well as in their effect on the environment controlled operations. Such reference mines could also provide the necessary information in respect of day-to-day running problems, required amounts of investment, minimum working capital, maintenance and repair needs and problems with unskilled labour drawn from the surroundings of such small mines, to mention only a few areas of missing experience.
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