Sublithospheric diamonds: Plate tectonics from Earth's deepest samples (Annual Reviews, 2024)
✦ A blue, boron-bearing diamond, with dark inclusions of a mineral called ferropericlase that was one of 26 inclusion-containing blue diamoids examined as part of a study of about 1000 blue diamonds (see: Smith, E. M., Shirey, S. B., Richardson S. H., Nestola, F., Bullock, E. S., Wang, J., & Wang, W. (2018) Blue boron-bearing diamonds from Earth’s lower mantle. Nature, 560 (7716), 84–87. http://doi.org/10.1038/s41586-018-0334-5). This gem weighs 0.03 carats. (Photo: Evan M. Smith/© 2018 GIA).