| marcasite (def. 1). |
[mahr-kuh-sahyt] 
| 1. | Also called white iron pyrites. a common mineral, iron disulfide, FeS2, chemically similar to pyrite but crystallizing in the orthorhombic system. |
| 2. | any of the crystallized forms of iron pyrites, much used in the 18th century for ornaments. |
| 3. | a specimen or ornament of this substance. |
[mahr-kuh-sit-i-kuhl] , adjective | mar·ca·site (mär'kə-sīt', -zīt') n.
[Middle English, from Medieval Latin marcasīta, from Arabic marqašīṯā, from Aramaic marqəšitā, from Akkadian marḫašu, from marḫaši, ancient region in the eastern Iranian plateau.] mar'ca·sit'i·cal (-sĭt'ĭ-kəl) adj. |
| white iron pyrites n. See marcasite. |
| marcasite (mär'kə-sīt', -zīt') Pronunciation Key
A light yellow to gray, metallic, orthorhombic mineral. Marcasite is a polymorph of pyrite and looks similar to it but has a lower specific gravity, is paler in color, and often has a radiating fibrous structure. Chemical formula: FeS2. |