Calcite, Marcasite
Blackstone Mine, Shullsburg, Upper Mississippi Valley District, Lafayette Co., Wisconsin, USA
Cabinet, 15.5 x 10.0 x 6.2 cm
Talk about cool; this is a BIG specimen of glittery golden-green marcasite that has formed a dome over massive sphalerite, crowned by a cluster of transparent, disc-shaped calcite crystals! In person, the calcites are clear to very slightly yellow (not pinkish as the camera seemed to make them). This is a large, dramatic old Shullsberg specimen! 15.5 x 10 x 6.2 cm