The Dynamic Earth View Multimedia Version

Main Menu >  GeoGallery >  Minerals >  Marcasite
TITLE: GeoGallery

Choose one of the following Minerals for more details:

Marcasite

Marcasite

Crystal formations such as this grow out of mineral-rich solutions in spacious rock cavities. When the solution becomes saturated, crystals begin to form on rock walls, on other crystals, or even on particles of dust. They grow quickly or slowly--or stop--depending on changes in temperature and the concentration of the solution. Marcasite forms from iron and sulfur to make crystals with a chemical composition of FeS2. Note how the size of the forming crystals grew larger with each round of formation in this specimen.


bottom navigation bar Smithsonian National Museum of Natural History Department of Mineral Sciences website Credits