PRESIDENTIAL ADDRESS — SECTION B. "JJ 



district, and the deposits of argentiferous galena found many 

 years ago at the Maitland Mine, to the west of Port Elizabeth. 



Of the manganese deposits, only three, according to Welsh,*, 

 are of any extent, and of these only one is really considerable, 

 containing possibly about 500,000 tons of ore. The exploitation 

 of this particular deposit, however, would hardly be feasible, 

 because it happens to be the site of the Caledon hot springs and 

 sanatorium. 



In the Milhvood goldfield, situated in the Outeniqua Moun- 

 tains, steeply folded shales and sandstones, believed to belong to 

 the Table Mountain sandstone series, are traversed by auriferous 

 quartz-veins, carrying pyrite, blende, galena, and sometimes 

 siderite. 



The occurrences are not worthy of exploitation, the small 

 quantities of gold won on these fields being all alluvial. 



Natural gas and petroleum may exist beneath the anticlines 

 into which the fossiliferous Bokkeveld beds have been thrown 

 between Touws River and Montagu, but it is a remote possibility. 



The most promising potential sources of mineral wealth in 

 the area are the occurrences of limestone, belonging to the Nama 

 system, that occur in the inliers already referred to. A deposit 

 of this nature is to form the basis of a large cement and lime- 

 works at Robertson, and the possibilities of another inlier between 

 Hankey and Port Elizabeth are being investigated with a view to 

 establishing cement works in that neighbourhood. 



The dolomite limestone of the Cango area will also, no doubt, 

 eventually become of importance as a source of " blue " lime. 



The clays and shales of the Cretaceous Uitenhage series 

 are made into good tiles, pipes, and bricks at several localities. 

 The formation also contains beds of lignite of inferior quality, 

 but efforts to utilise this material have not so far proved suc- 

 cessful. 



Certain sections of the southern coast of Cape Province, 

 included in the area, appear to be worth prospecting for rock 

 phosphate. 



The Kalahari Region. 



The Kalahari Region embraces the portion of the Kalahari 

 falling within the Union. No important mineral deposits have 

 been discovered within it, which is hardly a matter of surprise, 

 seeing that, in addition to being practically waterless, the greater 

 part of the area is covered with a deep mantle of sand and surface 

 limestone that completely obscure the underlying rocks. 



The only economic minerals hitherto discovered in the 

 Kalahari region are potassium nitrate and kieselguhr. The 

 former occurs in the Matsap salt-pan, but apparently not in 

 payable quantities. Kieselguhr is found in the Witkop pan in 



* Cf. Welsh, A. B. : Report on Manganese in the South-West Districts 

 of the Cape Proz'ince. Dept. of Mines and Industries, Union of South 

 Africa, 1917. 



