Actually, it is more like 300 million. The coal formed because plants produced lignin but there was no organism that was able to break it up, until fungi evolv

Actually, it is more like 300 million. The coal formed because plants produced lignin but there was no organism that was able to break it up, until fungi evolved. Now it is pretty much impossible for new coal to form in significant amount (except maybe for peat bogs) because every tree that falls will rot.