Does the article describe any theories as to how the quartzite ended up on the island? I skimmed it twice and searched for “why” and “theor” but failed to spot anything.
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Saindou Boura took us to meet his younger brother Mourchidi, his brother-in-law and a young nephew, who were digging in a manioc plot. In French, Hemond and Class went through a layman’s explanation of the rocks’ origins, venturing that the quartzite must have formed in Africa or Madagascar, then somehow ended up here when ancient landmasses rearranged themselves. Oh, you mean when Africa and Madagascar were part of Gondwanaland? queried Mourchidi Boura. At this, the scientists were dumbfounded: No non-geologist anywhere could be expected to know what Gondwanaland was, much less a farmer working the soil by hand on a tiny, remote island. Clearly, the scientists had underestimated these folks."