Pseudomorph Goethite After Marcasite | Prophecy Stone | 31 gr | Farafra Oasis, Egypt | SO24 Size:B Shape: Triangle Laser Cut

Shape: Triangle Laser Cut

We include 2 specimen cards but unfortunately the thin section and coin used in the ad are NOT included

derived from the more primitive Agoniatitida during the Middle Devonian some 390 million years ago

This specimen of Manganite is distinctive enough to show its true identity and is a beautiful and interesting specimen for display

Dimensions:   73x55x50 mm / 2

Pseudomorph Goethite After Marcasite | Prophecy Stone | 31 gr | Farafra Oasis, Egypt | SO24 Size:B Shape: Triangle Laser CutChoose your Pseudomorph! Pseudomorphs are mineral specimens that have the external shape of one mineral but are composed of another. The pseudomorph goethite after marcasite forms when marcasite is exposed to oxidizing conditions and starts to oxidize and break down. As the marcasite breaks down, goethite replaces it in the crystal structure, preserving the shape of the original marcasite crystal. The resulting specimen appears as a marcasite crystal,