The Birim basin is rich in minerals and has been a source of gold for centuries, the basis for the former name of Ghana: the
Gold Coast. It is also a major source of diamonds.
Gold king Kofi Kolkalli The Birim river gravels hold gold which has long been extracted through panning or
Placer mining, used in making ornaments and for trans-Saharan trade long before the Europeans discovered the Gold Coast. Starting in the late 19th century,
British gold mining companies adopted conventional mining and extraction processes, developing deep underground mines in the underlying Ashanti belt. After independence in 1957 the government nationalized the gold mining industry. With inadequate investment, the mines deteriorated and profitability fell. However, after privatization in 1992 the new owners injected capital, mostly into the Ashanti belt mines, discovering new world-class deposits. The Ashanti Belt now has an aggregated gold endowment of over 125,000,000 ounces of gold.
Diamonds Ghana has produced gems from alluvial gravels since the 1920s, mostly industrial grade. In the early 1990s the government announced plans to privatize its diamond-mining operations but found no buyers. The government still owns Ghana Consolidated Diamonds, since 2005 the only formal commercial producer of diamonds. Ghana Consolidated Diamonds uses a strip and mine method at their placer mine in Akwatia, using
Manitowoc draglines. The plant is old and obsolescent, available only 38% of the time and producing under capacity. The government is looking for a strategic investor to take over the mine. In 1989 the government of Ghana set up the Precious Minerals Marketing Corporation (PMMC) to promote small-scale gold and diamond mining and to purchase and resell the output. As much as 70% of the diamonds were smuggled out of the country before the PMMC was created. In its first sixteen months of operation, the PMMC bought of diamonds and 20,365 ounces of gold and sold of diamonds worth US$8 million. However, because of complaints over raw gem sales, the government in March 1992 ordered an investigation into the operations of the state agency and suspended its managing director. The available reserves cover an area of 240 km2 along the Birim River and are estimated to contain of proven reserve. Most of the diamond production in the Birim basin is now by artisanal miners from alluvial and in situ diamond deposits near Akwatia. There is some evidence that production volumes from these small-scale operations are increasing.
Bauxite The
Atewa Range at the headwaters of the river contains extensive
bauxite deposits with minor
kaolin occurrences, which are being evaluated by groups such as
BHP. However, the bauxite deposits are generally poor quality compared to larger deposits of higher-quality bauxite in nearby
Guinea and are in an environmentally sensitive area, so are unlikely to be developed. ==Farming==