niAIVIONDS OF GERMAN S.W. AFRICA. II3 



sandstone. When the coast had risen, and the quartzites 

 removed by weathering and deflation, the diamonds remained 

 behind and gradnally accumulated in the surface graveL There 

 is, however, no positive evidence available for connecting the 

 diamonds with the cjuartzite, for the reported discover}^ of some 

 diamonds in that rock (Merensky does not refer to this report in 

 his paper) is due to a misunderstanding by inexperienced observers. 



When I heard of this find, which had been made by a trust- 

 worthy person, I made inquiries, and was finally able to go to the 

 exact spot, about lo miles south of Prince of Wales Bay. Two 

 diamonds had been broken out of the stone or, rather, they had 

 dropped out when a piece of sandstone was broken up. That 

 stone was. however, not the cretaceous sandstone discovered and 

 described by Merensky, and fairly common in that part of the coun- 

 try, but an entirely recent formation. The locality was a broad 

 furrow running for several miles S.W. by N.E., and due to the 

 weathering of a d^^ke. about three feet thick. Within that furrow 

 sand had accumulated and become quite hard, like a real sandstone ; 

 but it was merely hardened sand, such as is formed every day 

 at the present time. With the sand, the diamonds had fallen 

 into that furrow and become encased in the hardening sand. On 

 the other hand, not a single diamond has been found as yet in 

 the cretaceous sandstone. 



A])art from that feature of Merensk^-'s theory, it was quite 

 possible that he was right in assuming that the diamonds had come 

 from the sea. 



Quite a different view was expressed b}' Dr. Lotz*. who, briefly 

 stated, assumes that the diamonds originally had come from the 

 area of the Vaal River, and that they were carried into the sea 

 by the Orange River. The distribution along the coast belt would 

 have been effected by ocean currents, and finally the wind would 

 have transported them in a northerly direction. 



It must be admitted that the occurrence of numerous water- worn 

 pebbles of agates, etc., along the present coast, as far north as 

 Walfish Bay, as well as some miles inland, at an altitude of at least 

 150 feet above the present sea level, made that view appear quite 

 feasible, for the pebbles were in many cases quite similar to those 

 found in and about the Vaal, and were evidently derived from 

 the same rocks. 



On the other hand, we must consider that the Vaal River deposits 

 were 500 miles away, and that, in spite of much prospecting along 

 the Vaal and Orange Rivers, no other alluvial deposits have been 

 found as yet ; hence it does not appear very probable that the 

 diamonds of German South-W^est Africa had travelled all that 

 distance, although the pebbles undoubtedly had done so. Hence 

 I prefer to share the view of Mr. J. Kuntz,t who said, in reply to 

 Dr. Lotz's paper : " It is possible that the agate-pebbles, etc., do 

 come from the Orange River, but the diamonds have probably a 

 nearer source, which is at present either hidden by the sea or still 

 to^be discovered in the desert near by." 



* Lotz, H., Mon. Ber. Deutsch. Geol. Ges., 1909, No. 3. 

 t Kuntz, J., Mon. Ber. Deutsch. Geol. Ges., 1909, No. 4. 



