Marcasite
Pronunciation : Mar"ca*site
Part of Speech : n.
Etymology : [F. marcassite; cf. It. marcassita, Sp. marquesita, Pg. marquezita; all fr. Ar. marqashitha.] (Min.)
Definition : Defn: A sulphide of iron resembling pyrite or common iron pyrites in composition, but differing in form; white iron pyrites. Golden marcasite, tin. [Obs.]
Source : Webster's Unabridged Dictionary, 1913