Roger Weller, geology instructor
firstname.lastname@example.org copyright 2010-R.Weller
Marcasite has the same chemical composition as pyrite, iron sulfide, but unlike pyrite
(which is Cubic), marcasite is Orthorhombic.
Photo is copyright free only for non-commercial educational uses.
Just credit photo to R.Weller/Cochise College.
Specimen from the Cochise College collection