Kimberlites and the mantle

During the quadriennal period 1975 to 1978 a considerable number of investigations, often closely related, have been undertaken on kimberlites, mantle xenoliths and diamonds. Much progress was made into our knowledge of specific occurrences of kimberlite and diamond in the United States. However, these works are few when compared with the large number of studies carried out on Southern African kimberlites and xenoliths, many by scientists in U.S. institutions. Since the mecca of kimberlite, xenoliths and diamonds in South Africa, particularly Kimberley, it is difficult and unwarranted to separate out the various investigations by nationality.