marcasite

noun

mar·​ca·​site ˈmär-kə-ˌsīt 

-ˌzīt;

ˌmär-kə-ˈzēt

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

: 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

Word History

Etymology

Middle English marchasite, from Medieval Latin marcasita

First Known Use

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