billon

/ˈbɪlən/
noun
  1. An alloy of a precious metal (such as silver) with a majority base metal (such as copper), used especially in coins.
    • Billon was cheaper than pure silver for everyday currency.
    • The museum displayed a collection of billon coins from the Roman Empire.
    • Ancient coins were often made of billon to save on silver.
Synonyms
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