MADISON, Wis., Feb. 24 (UPI) -- A tiny zircon crystal from Australia, 4.4 billions years old, has been confirmed as the oldest discovered fragment of Earth's crust, scientists say.
A study of the crystal, led by University of Wisconsin-Madison geoscience Professor John Valley, shows the Earth's crust first formed just 160 million years after the formation of the solar system, the university reported Monday.