An 1812 Joao VI prince regent gold ingot of Sabara sold for $199,750 at Heritage Auctions' World and Ancient Coins auction in Long Beach, which ended on October 1.
Circulated in Brazil for a brief period between 1778 and 1833, the gold ingots are among the world's rarest numismatic items.
Just over 200 examples are known to exist, with very few still accompanied by their guia - a certificate indicating the ingot's value.
The guia sold alongside this particular example was in near original condition, which is unprecedented.
Other top lots included a South African Burgers Pond "coarse beard" coin, one of only 142 ever minted, which realised $152,750.
A Titus "Coliseum" sestertius, struck under Roman emperor Titus to mark the opening of the coliseum, achieved $146,875 - more than double its pre-auction estimate.
A Polish Danzig ducat from 1547, the first example to be offered at auction in decades, was hotly contested at the sale. It eventually made $135,125, dwarfing its $40,000 valuation.
Cristiano Bierrenbach, executive vice president of international numismatics, commented: "Heritage's growth in the World and Ancient Coin market has a bright future,"
"Long Beach Expo has always been a highlight of our hobby, but this year's results far surpassed our expectations. We remain grateful to our consigners and buyers and look forward to offering many special collections in the next year."
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