Articles | Volume 32, issue 1
Eur. J. Mineral., 32, 171–185, 2020
Eur. J. Mineral., 32, 171–185, 2020

Research article 11 Feb 2020

Research article | 11 Feb 2020

Breyite inclusions in diamond: experimental evidence for possible dual origin

Alan B. Woodland et al.

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Cited articles

Akaogi, M., Yano, M., Tejima, Y., Iijima, M., and Kojitani, H.: High-pressure transitions of diopside and wollastonite: phase equilibria and thermochemistry of CaMgSi2O6, CaSiO3 and CaSi2O5CaTiSiO5 system, Phys. Earth Planet. In., 143–144, 145–156, 2004. 
Anzolini, C., Angel, R. J., Merlini, M., Derzsi, M., Tokár, K., Milani, S., Krebs, M. Y., Brenker, F. E., Nestola, F., and Harris, J. W.: Depth of formation of CaSiO3-walstromite included in super-deep diamonds, Lithos, 265, 138–147, 2016. 
Anzolini, C., Prencipe, M., Alvaro, M., Romano, C., Vona, A., Lorenzon, S., Smith, E. M., Brenker, F. E., and Nestola, F.: Depth of formation of super-deep diamonds: Raman barometry of CaSiO3-walstromite inclusions, Am. Mineral., 103, 69–74, 2018. 
Berman, R. G.: Mixing properties of Ca–Mg–Fe–Mn garnets, Am. Mineral., 75, 328–344, 1990. 
Brenker, F., Nestola, F., Brenker, L., Peruzzo, L., Secco, L., and Harris, J. W.: Breyite, IMA 2018-062, CNMNC Newsletter No. 45, October 2018, Mineral. Mag., 82, 1225–1232, 2018. 
Short summary
We experimentally explored direct entrapment of breyite (CaSiO3) by diamond at upper-mantle conditions in a model subducted sediment rather than formation by retrogression of CaSiO3 perovskite, implying a deeper origin. Anhydrous low-T melting of CaCO3+SiO2 precludes breyite formation. Under hydrous conditions, reduction of melt results in graphite with breyite. Thus, breyite inclusions in natural diamond may form from aragonite + coesite or carbonate melt at 6–8 GPa via reduction with water.