Jul 16, 2020
Pyritized Ammonite
In environments with low oxygen, but high iron, fossils can sometimes be replaced with pyrite. With this ammonite here, the mineral has replaced the original material to provide a beautiful golden sheen.
A negative of this - in places with high humidity, the pyrite will start to rot the fossil. This is known as Pyrite Disease. My first big find - a Triceratops vertebrae&ribs - had unfortunately suffered this.The fossils, from a distance, looked fine, but on closer inspection the ribs had splintered into fine mulch, and only one vert was actually salvageable.
Depending on the context, this pretty mineral can be a boon or a bane (and sometimes both).