mar·​ca·​site ˈmär-kə-ˌsīt How to pronounce marcasite (audio)
: crystallized pyrite
: a pale yellow to white mineral of the same composition and appearance as pyrite but of different crystalline organization and lower specific gravity
: a piece of marcasite used in jewelry

Examples of marcasite in a Sentence

Recent Examples on the Web There's ample evidence that Neolithic hunter-gatherer groups and later cultures without access to steel would strike flint against pyrite or the closely related mineral marcasite. Gemma Tarlach, Discover Magazine, 19 July 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'marcasite.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Middle English marchasite, from Medieval Latin marcasita

First Known Use

15th century, in the meaning defined at sense 1a

Time Traveler
The first known use of marcasite was in the 15th century

Dictionary Entries Near marcasite

Cite this Entry

“Marcasite.” Dictionary, Merriam-Webster, Accessed 21 Feb. 2024.

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