Pyritized Fossils

"How Pyritized Fossils Form

​Have you ever seen a fossil that looked as though it were carved from pure gold? Chances are you were looking at an example of pyritization [pyritisation if you're a fan of British spelling]. It may not be made of precious gold, but it's an entirely natural fossil formation.

Pyrite, often called Fool's Gold, is an iron sulfide, and a very common mineral. Because of its shiny, metallic golden color, it has often been mistaken for true gold. It is brittle, and sadly subject to decay in moist environments, making it useless for most practical purposes. Nonetheless, it makes beautiful decorative mineral specimens!

Pyrite replacement of fossils is often caused by bacteria, in a process called permineralization..."

Rockhound Times, How Pyritized Fossils Form. 2021

Fossilized fool's gold turned out to be iron. This was known recently, however this was portrayed in the Quran 1400 years before it was discovered.