\Mar"ca*site\, n. [F. marcassite; cf. It. marcassita,
Sp. marquesita, Pg. marquezita; all fr. Ar. marqash[=i]tha.]
(Min.)
A sulphide of iron resembling pyrite or common iron pyrites
in composition, but differing in form; white iron pyrites.

{Golden marcasite}, tin. [Obs.]