Ferropericlase

Ferropericlase is a magnesium/iron oxide that is interpreted to be one of the main constituents of the earth's mantle together with a magnesium /iron silicate with a Perovskite structure. Ferropericlase has been found as inclusions in a few natural diamonds. An unusually high iron content in one suite of diamonds has been associated with an origin from the lowermost mantle [ [http://gac.esd.mun.ca/GAC_2006/search_abs/sub_program.asp?sess=98&form=10&abs_no=301 Kopylova, M.G. 2006. Ferropericlase from the lowermost mantle and its geodynamic significance] ] .

pin transition zone

Changes in the spin state of electrons in iron in mantle minerals has been studied experimentally in Ferropericlase. Samples are subject to the conditions of the lower mantle in a laser-heated diamond anvil cell and the spin-state is measured using synchrotron X-ray spectroscopy. Results indicate that the change from a high to low -spin state in iron occurs with increasing depth over a range from 1000 km to 2200 km [ [https://publicaffairs.llnl.gov/news/news_releases/2007/NR-07-09-03.html Researchers locate mantle’s spin transition zone, leading to clues about earth’s structure ] ] . The change in spin state is expected to be associated with a higher than expected increase in density with depth.

References

ee also

Post-perovskite