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noun mar·ca·site \ˈmär-kə-ˌsīt, -ˌzīt; ˌmär-kə-ˈzēt\

Definition of marcasite

  1. 1 a :  crystallized pyrite b :  a pale yellow to white mineral of the same composition and appearance as pyrite but of different crystalline organization and lower specific gravity

  2. 2 :  a piece of marcasite used in jewelry

Origin and Etymology of marcasite

Middle English marchasite, from Medieval Latin marcasita

First Known Use: 15th century

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