sought-after ! Pyrite nodule

Pyrite concretion
These gorgeous and interesting pyrite concretions fall into that category of odd, exquisite, curious, and weird. My favorite category! A fun add to any collection, especially for pyrite collectors, or concretion lovers.

Concretions are found in sedimentary rock or soil, often ovid or spherical in shape. They generally form around some type of nucleus, usually early on in the burial history of the sediment. This makes them harder than the surrounding host sediment. Record of these geological curiosities dates back to the 18th century. They were often confused with fossils of dinosaurs, plants, humans and extraterrestrials. The name concretion is derived from Latin; con (together), crescere (grow).

This specimen was collected from marine shales in Guangxi, China. The slightly ovoidal nodule consist of layers of pyrite, or iron disulfide, and black shale material, and sits nicely without support.