"what could be easier than accumulating wealth by hiring people to dig stuff from the ground and ship it abroad?". One would think this but look at what is happening in South Africa due to the declining state-owned railways: (https://www.economist.com/middle-east-and-africa/2023/01/17/south-africas-disintegrating-freight-railway-is-crippling-firms). As you have mentioned, mining is incredibly capital intensive — the JSE was founded in the 1880s to help dig the gold below Johannesburg. Combine this with Africa’s lack of domestic capital and high cost of borrowing might also contribute to explaining the lack of resource sector billionaires.
"what could be easier than accumulating wealth by hiring people to dig stuff from the ground and ship it abroad?". One would think this but look at what is happening in South Africa due to the declining state-owned railways: (https://www.economist.com/middle-east-and-africa/2023/01/17/south-africas-disintegrating-freight-railway-is-crippling-firms). As you have mentioned, mining is incredibly capital intensive — the JSE was founded in the 1880s to help dig the gold below Johannesburg. Combine this with Africa’s lack of domestic capital and high cost of borrowing might also contribute to explaining the lack of resource sector billionaires.