"Detailed study of diamondiferous rocks in South Africa: geology of kimberlite occurences, pipe morphologies, pipe minerals, other types of kimberlite bodies, inclusions in kimberlites and mineralogy of the same, the diamond and its genesis. One of the earlies studies attempting to explain the nature of kimberlites, inclusions in same, and both their origin and the origin of diamonds, with very little said about the diamonds themselves." (Sinkankas)