Strangely enough, experts have never physically seen what they theorize is Earth's most abundant mineral, until now. Finding traces of this mineral in a meteorite, researchers finally have enough hard physical evidence of its existence and properties to give it a name - bridgmanite.
Oliver Tschauner of the University of Nevada-Las Vegas and Chi Ma of the California Institute of Technology (Caltech) have been working to characterize and determine the chemical properties of bridgmanite - formerly known as silicate-perovskite - since 2009.
Prior to this work, there had been no concrete evidence that silicate-perovskite even existed, despite the fact that geological know-how dictated that it must exist, and in vast quantities.
"This finding fills a vexing gap in the taxonomy of minerals," Tschauner said in a statement.
According to the researchers, a mineral that can remain stable even under high-pressure and high-temperature conditions is absolutely necessary to make up the majority of the Earth's lower mantle. Seismic data has revealed long ago that this vast region of the Earth is undoubtedly solid, and models of the Earth's structure allowed researchers to conclude that this mineral is likely the most abundant mineral in the Earth. However, being buried so deep beneath the planet's surface, there was very little chance geologists would ever be able to physically see it.
Then Ma and Tschauner started running tests on a sample from the Tenham meteorite, which fell to Earth in 1879.
Because the meteorite had been through countless high-energy collisions, the geologists theorized that conditions were similar enough to form the elusive mantle mineral.
Sure enough, the resulting tests confirmed the presence of tiny silicate-perovskite-like crystals throughout the sample.
"It is a really cool discovery," Ma said. "Our finding of natural bridgmanite not only provides new information on shock conditions and impact processes on small bodies in the solar system, but the tiny bridgmanite found in a meteorite could also help investigations of phase transformation mechanisms in the deep Earth"
After five years of testing this mineral's properties to its fullest extent, the researchers finally gathered enough information to earn the mineral a new and official name.
They named it bridgmanite, after Nobel Prize winning physicist Percy W Bridgman - whose work, appropriately, focused on the effects of high pressures on materials.
The name was officially confirmed June 2, according to the American Geophysical Union.