Breyite is a high pressure calcium silicate mineral (CaSiO
3) found in diamond inclusions.
It is the second most abundant inclusion after
ferropericlase, for diamonds with a deep Earth origin.
Its occurrence can also indicate the host diamond's super-deep origin. This mineral is named after German mineralogist, petrologist and geochemist Gerhard P. Brey.

References
Silicate minerals
Calcium minerals
High pressure science
Diamond
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