In March 2026, one of Ghana's own mining companies said it would invest about $1.2 billion in its operations at the Tarkwa and Damang gold mines. Both sit on the Ashanti belt, one of three narrow bands of ancient rock that carry almost all of Ghana's gold. Those belts, mapped above, are the reason the country's mines cluster where they do. More than a century after large-scale mining began, they are still drawing fresh capital, from Ghanaian and international investors alike.

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Gold Follows the Faults

Ghana's gold is not spread evenly across the country. It runs in belts, long narrow bands of ancient rock, and within them it clusters along deep fractures in the crust called shear zones. Billions of years ago, hot mineral-rich fluids rose up through these shear zones and faults in Ghana's Birimian rock and left gold behind as they cooled. Because the fluids followed the same great faults, so does the gold, tracing lines that run from the southwest to the northeast, the very lines geologists still follow to explore today.

How tightly the gold clusters is striking. A detailed geological study of the Kumasi Basin, the broad stretch of ground between the Ashanti and Sefwi-Bibiani belts, found that roughly 99% of its known gold occurrences sit within ground making up less than a third of the area. That is why Ghana's mines line up along the belts rather than scattering at random, and why the country's two very different deposit types, lode gold in quartz veins and Tarkwaian gold in ancient river gravels, still appear along the same trends.

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Belt Where it runs Rock type Selected mines What sets it apart
Ashanti Eastern trend, running inland from near the Atlantic coast Volcanic (greenstone) belt Obuasi, Tarkwa, Damang, Iduapriem Hosts many of Ghana's largest and oldest mines, and both of the country's gold types: quartz-vein lode and river-gravel Tarkwaian
Sefwi-Bibiani Western trend, parallel to Ashanti, continuing toward Côte d'Ivoire Volcanic (greenstone) belt Bibiani, Chirano, Ahafo Gold follows the Bibiani shear zone, and the belt continues across the international border
Asankrangwa Central corridor, between the other two, along the Kumasi Basin Shear-zone corridor (not a volcanic belt) Asanko Gold Mine A line of gold-bearing fractures through the basin, and the last of the three to be recognised

Geology per Chudasama et al. (2016), Ore Geology Reviews 78; mines per company disclosures.

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Why the Middle Belt Is Different

The three belts are not the same kind of thing. Ashanti and Sefwi-Bibiani are volcanic belts, built from ancient lava and ash that hardened more than two billion years ago. The middle one, Asankrangwa, is different in kind: rather than a belt of volcanic rock, it is a line of gold-bearing fractures running down the centre of the basin between the other two.

That difference helps explain why it was the last of the three to be understood. Where the older belts reach the surface, much of the Asankrangwa ground lies buried under younger river sediments and soil, a cover that kept it out of view for early prospectors. For a long time it was worked mainly by small-scale and colonial-era miners, and its gold-bearing structure was, per the same study, not fully recognised until the mid-1990s, generations after mining had taken hold on its neighbours.

It is the belt that hosts Galiano Gold's Asanko mine, sitting between the two older and better-known trends.

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The Belts Keep Drawing Capital

More than a century of mining has not exhausted the interest in these belts. In March 2026, Engineers & Planners, a wholly Ghanaian-owned mining company, said it would invest about $1.2 billion in its operations at Tarkwa and Damang, two long-running mines on the Ashanti belt, backed by a fleet of new heavy mining equipment. International capital is moving too: in 2025, Zijin Mining completed a $1 billion acquisition of the Akyem mine in Ghana's Eastern Region. The rock was set two billion years ago; the money committed to working it is being put down this year.

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