Geochemistry of peridotitic clinopyroxene from the diamondiferous Mbuji-Mayi and Tshibwe kimberlites (DRC): insight into the compositional and thermal state of the SCLM beneath the eastern Kasai craton - Nkere, B.J.; Janney, P.E. (International Kimberlite Conference: Extended Abstracts, 2017)