Superb and uncommon pyrite epimorph after calcite from Charcas, Mexico. Epimorph is a type of pseudomorph where a mineral replaces another mineral only at the surface, forming a cast. The primary sharp and very flat tabular calcite crystals are pseudomorphed by sparkling pyrite. The color is bright brassy-yellow and the crystals sparkle strongly. It is complete all over and almost a complete floater. For references see the 2024 issue of The Mineralogical Record vol. 55, # 6. In very good condition – some small contacts.

Outstanding epimorph!