Australians find extremely rare mineral in meteorite impact crater

A group of scientists has discovered one of the rarest minerals on Earth buried deep within what may be the largest-known meteorite impact crater in Australia.

The ultra-rare mineral known as reidite was found by Curtin University researchers in the long buried Woodleigh Crater near Shark Bay, Western Australia, about 750 km. north of Perth.

Reidite only forms in rocks that experience the incredible pressure created when rocks from space slam into the Earth's crust, the team explains in a paper published in the Geology journal.

The mineral starts as the common mineral zircon and transforms to reidite during the pressure of impact, making it incredibly rare and only the sixth-known crater on Earth where the mineral has been found.

Honours student Morgan Cox, from Curtin's School of Earth and Planetary Sciences. (Image courtesy of Curtis University.)

The chance find of reidite gave the team new insights into how the Earth responds to the dramatic changes created by meteorite impact, a process that violently lifts deep-seated rocks to the surface in seconds.

According to Curtis University it's only the sixth time the mineral has been discovered on Earth.

Research supervisor Aaron Cavosie noted the drill core sampled the middle of the impact crater, a region called the central uplift.

The discovery suggest that the Woodleigh Crater may be much larger than previously thought. It has long been buried beneath younger sedimentary rocks, so its size is not yet known and remains debated.

Previous research estimated the crater to be between 60-120km in diameter.

The team from Curtis University is currently using numerical modelling to refine the size of the crater.