web analytics

Earth’s Most Abundant Mineral Finally Given a Name


Image credit: Tschauner et al., 2014, Science/AAAS

Although it consists of a third of the Erath, the world’s most abundant mineral has not got its name for a quite long time,  scientists was unable to get a natural sample of it to characterize.

At present, after nearly intensive searching for fifty years, scientists have found a specimen within a meteorite slamming into our planet in 1879, which meant such anonymous mineral could be named in the end. Being characterized in the journal Science, this mineral, would be named as bridgmanite in honor of Percy Bridgman, an American physicist and 1964 Nobel laureate, who was the pioneer of development of those techniques, which made it possible for  scientists to synthesize and analyze minerals at pressures similar to those experienced deep within our planet.

The lower mantle of the Earth consists of nearly fifty percent of the planet by volume, extending from 670 to 2,900 kilometers in regard to depth. Pressures in this region starts at 237,000 times the atmospheric pressure (24 gigapascals) and in some cases, they could get to 1.3 million times atmospheric pressure.

Even if scientists have little information about the lower mantle, they think it could comprise a super-dense version of magnesium iron silicate. The reason why such mineral has got its name is that scientists fail to find a natural sample in reality. According to requirement of the International Mineralogical Association, a mineral should be analyzed in its natural state before it could be named. Although it consists of nearly thirty-eight percent of the entire volume of our planet, it is still very difficult to find it, because it is very rare at the surface of the Earth, and it is generally stable at pressures found more than 670 kilometers below the surface.

Finally, scientists were capable of obtaining a natural sample thanks to an asteroid collision, which occurred hundreds of millions of years ago. As a result of that event, a meteorite had been slammed into Australia in 1879. Such meteorite was subjected to temperatures of around 2100oC and pressures of 24 gigapascals, which in some way is just like the conditions experienced quite deep within the Earth. After careful examination of the specimen, scientists found microscopic pieces of the mineral buried in the meteorite’s veins. When the rock was taken back to ambient temperature and pressure, the mineral should have decayed, however the icy temperatures of space served as a preservative, thus actually freezing it into place.

While scientists are finally able to name the mineral, this discovery is quite vital, because it would be much helpful for us to know more about the region of Earth where it was discovered. By the analysis of the elements fitting into its crystal structure, scientists would be capable of making improvement of existing models to show the behavior of the lower mantle .

The mineral’s new name, bridgmanite, is in honor of Percy Bridgman, a scientist who won the 1946 Nobel Prize in Physics. Bridgman pioneered techniques that allowed scientists to synthesize and analyze minerals at pressures akin to those experienced deep within our planet.

Source: ScienceSciencemag, and New Scientist

Journal reference: Tschauner, Oliver, et al. “Discovery of bridgmanite, the most abundant mineral in Earth, in a shocked meteorite.” Science 346.6213 (2014): 1100-1102.

You May Also Like:

What Happens if You Stick Your Hand into “Hot Ice”?
Supercooled Helium Defies Gravity
What Is The Earth Worth?
Chemistry Life Hacks