Pyrite or iron disulfide was called fool's gold because foolish prospectors would mistake it for real gold. But research showed that pyrite can actually contain real gold!
From The Conversation:
When crystals stretch or twist, the bonds between neighbouring atoms are broken and remade, forming billions of tiny imperfections called “dislocations”, each roughly 100,000 times smaller than the width of a human hair, or 100 times smaller than a virus particle.
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Our research reveals that dislocations within pyrite crystals can be “decorated” with gold atoms. This is particularly common where the crystals have been twisted during their history; here, gold can be present at concentrations several times higher than in the rest of the crystal.
Image: Uoaei1/Wikimedia Commons
Gold (Au) atoms hiding within a pyrite crystal, alongside other imperfections including nickel, copper and bismuth. Scale bar indicates 20 nanometres. Image: Denis Fougerouse/Curtin University
