Countries like the US, Russia, China, Canada, Brazil, and Australia are relatively rich in a wide variety of mineral resources for a simple reason: they’re big. Big enough to have a lot of geology, a lot of environments, a lot of situations where economic mineral deposits can accumulate.
Small countries just don’t have the geologic diversity to be rich in lots of minerals—but lucky geologic accidents do occur, sometimes making a small country the world leader in one or two commodities.
For example, Spain and Italy together account for two-thirds of the world’s reserve base of mercury. Spain’s mercury mines were among the oldest mines of any type in continual operation (since Roman times) when they ceased mining in 2003 because of decreasing demand for mercury. Pumice, a volcanic rock used in building-block construction, spews from volcanoes all over the world, but Greece produces more commercial pumice than any other nation. Finland produces more than a third of the world’s peat. The US imports nearly a million tons of peat annually for horticulture, but next-door Canada is the main supplier rather than Finland.
Botswana’s miners find more gem diamonds than miners elsewhere, at 25 million carats per year, but Russia is a close second with 23 million per year. Botswana and adjacent parts of southern Africa harbor a disproportionate number of kimberlite pipes, unusual igneous rocks that transport diamonds from depths of 150 to 200 km beneath the surface—depths where pressures are great enough to squeeze carbon into diamonds.
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Gem tourmaline photo from Wikipedia under GNU Free Documentation License.
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