Simbercite with Pyrite Necklace in Sterling1. 2" x 1. 5" Pyrite Simbercite Simbercite, named for the Russian city of Simbirsk, is a rare agatized fossil that filled ancient ammonite chambers over millions of years. Its complex mineral compositionincluding pyrite veins that trace the creature's original skeletal structurecreates a sophisticated blend of geology and paleontology. This sterling silver necklace honors both the stone's natural beauty and its deep temporal origins. In this cabochon