By the late 1970s, it had been proposed that the seismic discontinuity at about 660 km in the mantle represented a change from spinel structure minerals with an olivine composition to silicate perovskite with ferropericlase.
[2][3] In 2014, the Commission on New Minerals, Nomenclature and Classification (CNMNC) of the International Mineralogical Association (IMA) approved the name bridgmanite for perovskite-structured (Mg,Fe)SiO3,[1] in honor of physicist Percy Bridgman, who was awarded the Nobel Prize in Physics in 1946 for his high-pressure research.
B is another metal that forms smaller cations, typically silicon, although minor amounts of ferric iron and aluminum can occur.
In pyrolitic and harzburgitic lithogies, bridgmanite constitutes around 80% of the mineral assemblage, and calcium perovskite less than 10%.
[3] Calcium silicate perovskite has been identified at Earth's surface as inclusions in diamonds.
With the great mechanical strength of the diamonds a large part of this pressure is retained inside the lattice, enabling inclusions such as the calcium silicate to be preserved in high-pressure form.