Fool’s gold is providing scientists with valuable insights into a turning point in Earth’s evolution, which took place billions of years ago. Scientists are recreating ancient forms of the mineral pyrite — dubbed fool’s gold for its metallic lustre — that reveal details of past geological events.
Detailed analysis of the mineral is giving fresh insight into Earth before the Great Oxygenation Event, which took place 2.4 billion years ago. This was a time when oxygen released by early forms of bacteria gave rise to new forms of plant and animal life, transforming Earth’s oceans and atmosphere.
Studying the composition of pyrite enables a geological snapshot of events at the time when it was formed. Studying the composition of different forms of iron in fool’s gold gives scientists clues as to how conditions such as atmospheric oxygen influenced the processes forming the compound.
The latest research shows that bacteria — which would have been an abundant life form at the time — did not influence the early composition of pyrite. This result, which contrasts with previous thinking, gives scientists a much clearer picture of the process