April 17 (UPI) -- Researchers have identified the "ghosts" of a new mineral at a pair of ancient meteorite impact sites.
The mineral is a new type of monazite, which only forms under the high-pressure conditions created by meteorite impacts.
Scientists found the new mineral after examining rock samples from impact craters in Germany and Canada. Researchers used an electron scanning microscope to study the tiny rock fragments.
"We found microscopic evidence that monazite, a rare earth element phosphate, transformed to another crystal structure under high pressure from a shockwave, similar to how graphite can turn into diamond under pressure," Nick Timms, an associate professor of earth and planetary sciences at Curtin University in Australia, said in a news release.
Interestingly, the new mineral form didn't last. It came and went. But Timms and his colleagues were able to see the mineral's ghostly signature.
"The mineral reverted to its original crystal structure instead of maintaining this new structural form, and while the new mineral only existed for fractions of a second as the shockwave passed through the Earth close to ground zero, it left unique crystallographic clues to its existence," Timms said.
Timms suggests it's possible scientists will never directly observe the new mineral.
"The mineral is not stable at the Earth's surface and readily transforms back to monazite again," he said. "Therefore, we have really only seen, and will probably only ever see, its 'ghost.'"
Researchers described their ghostly discovery this week in the journal Geology.