Everyone knows that Australia is old. Just how old has been defined by science - A zircon crystal on a Western Australian sheep station is the oldest piece of planet Earth. It is 4.4 billion years old.
Tests were done to determine the crystal's age. The rate of decay of uranium against the constant lead showed how old it was. This was confirmed by atom-probe tomography where the mass of lead atoms is measured.
The zircon particle was created on the Earth's crust soon after the planet formed. And the Earth was not a violent place until much later. Water was already present and there is a high probability that life began at this time. The Hadean eon as this period is called in now a misnomer because it means Hadean the god of hell.
Proof of life is unlikely. Science is not advanced enough yet to fully examine this period. Very little can be identified as originating in this period of the Earth's development.
Science by Ty Buchanan