This grant will allow the completion of PhD dissertation research by F. A. Caporuscio who will analyze 12 samples of eclogite inclusions from the Bellsbank and Roberts-Victor kimberlites, South Africa. Electron microprobe and petrographic analyses will be completed; chemical analyses on mineral seperates and some whole rocks will be carried out for rare-earth elements as well as Ba and Hf; Oxygen isotopes will be determined for whole rocks and mineral seperates; and Nd and Sr isotopic analyses will be carried out on selected samples. The purpose is to better understand the chemistry and history of the mantle underlying the old and stable crust of southern Africa.