Basic Diamond Info

✦ 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).

General review of the geological aspects of diamond formation:

Shirey, S.B., and Shigley, J.E., 2013, Recent advances in understanding the geology of diamonds: Gems & Gemology, v. 49, 188–222. http://dx.doi.org/10.5741/GEMS.49.4.188


How do most diamonds form?:

Smit, K. V. and Shirey, S.B. (2018) How do diamonds form in the deep Earth? Gems & Gemology 54: 440–445. https://www.gia.edu/gems-gemology/winter-2018-how-do-diamonds-form-in-the-deep-earth


How do big diamonds form deep in the mantle?:

Smith, E. M., Shirey, S. B. & Wang, W. (2017) The very deep origin of the world's biggest diamonds. Gems & Gemology, Vol. 53, No. 4, pp. 388–403. https://www.gia.edu/gems-gemology/winter-2017-worlds-biggest-diamonds


Diamonds and how does water cycles into the deep Earth?:

Smit, K. V. and Shirey, S. B.​ (2018) Diamonds help solve the enigma of Earth's deep water, Gems & Gemology, Vol. 54 (no. 2) 220-223. https://www.gia.edu/doc/Summer-2018-Gems-Gemology.pdf


How do diamonds get to the surface?:

Smit, K. V. and Shirey, S.B. (2019) Kimberlites: Earth’s Diamond Delivery System. Gems & Gemology 55: 270-276. https://www.gia.edu/gems-gemology/summer-2019-kimberlites-earths-diamond-delivery-system


How can we know how old diamonds are?:

Smit, K. V. and Shirey, S.B. (2019) How Old Are Diamonds? Are They Forever? Gems & Gemology 55: 102–109. https://www.gia.edu/gems-gemology/spring-2019-how-old-are-diamonds-are-they-forever


What happens to a diamonds during eruption?:

Smit, K. V. and Shirey, S.B. (2020) Diamonds are not forever! Diamond dissolution. Gems & Gemology 56: 148–155. https://www.gia.edu/gems-gemology/spring-2020-diamond-dissolution


Advances in diamond research with the Deep Carbon Observatory (DCO) 2011-2019:

Shirey, S., Smit, K., Pearson, D., Walter, M., Aulbach, S., Brenker, F. E., Bureau, H., Burnham, A. D., Cartigny, P., Chacko, T., Frost, D. J. , Hauri, E. H., Jacob, D. E., Jacobsen, S. D., Kohn, S. C., Luth, R. W., Mikhail, S., Navon, O., Nestola, F., Nimis, P., Smith, E. M., Stachel, T., Stagno, V., Steele, A., Thomassot, E., Thomson, A. R., Weiss, Y. (2019). Diamonds and the Mantle Geodynamics of Carbon: Deep Mantle Carbon Evolution from the Diamond Record. In B. Orcutt, I. Daniel, & R. Dasgupta (Eds.), Deep Carbon: Past to Present (pp. 89-128). Cambridge: Cambridge University Press. doi:10.1017/9781108677950.005. https://www.cambridge.org/core/books/deep-carbon/diamonds-and-the-mantle-geodynamics-of-carbon/E46212484DDAA32B1DA14B796EB3D9BC


Summary of recent scientific research on diamonds for the specialist:

Shirey, S.B., Cartigny, P., Frost, D.J., Keshav, S., Nestola, F., Nimis, P., Pearson, D.G., Sobolev, N.V., and Walter, M.J. (2013) Diamonds and the Geology of Mantle Carbon: Reviews in Mineralogy and Geochemistry, v. 75, p. 355–421. http://doi.org/10.2138/rmg.2013.75.12


Diamonds as a mantle sample —the state of the art in 2003:

Pearson, D.G., Canil, D., and Shirey, S.B. (2003) Chapter 7 - Mantle samples included in volcanic rocks: xenoliths and diamonds, in Carlson, R.W., ed., Teatise On Geochemistry: Vol. 2, The Mantle: New York, Elsevier, p. 171-277. https://www.sciencedirect.com/science/article/pii/B0080437516020053?via%3Dihub