Calcite with Pyrite and Marcasite

Add Chicago to your list of Calcite localities! This calcite miniature is a fine example of a new find recently made. Apparently Conco, an aggregate mining company tunnels throughout the greater Chicagoland area. An enterprising geologist has managaed to gain access to the occasional pockets of Calcite they encounter. This piece comes from the first pocket of Scalenohedral calcites found in the area. Apparently there are Thalassinoides Burrows (ancient burrowing Shrimp), that created space for the calcites to later grow. It has internal "gold glitter," from the Marcasite and Pyrite included inside it. it also has a phantom in the primary crystal. The pics show front and back of the specimen. No apparent damage.