202 MANGANESE IN THE CAPE COLONY. 



A sample sent from Knysna gave 52 per cent, of metallic 

 manganese and i^ per cent, of phosphoric oxide, while another 

 from Xamaqnaland gave nearly 56 per cent, of metallic man- 

 ganese. Unfortunately details are wanting as to the conditions 

 of the occurrence of the ore at these two places. 



Tlic manganese industry seems to depend entirely on the 

 facilities for shipping. The quality and quantity of ore, so far 

 found, do not seem to warrant the expense of mining at all the 

 localities where the ore has been discovered. If the deposits 

 hitherto discovered are the richest existing in this neighbourhood, 

 then I am afraid only those on the coast can be worked, unless 

 the price of manganese goes up or the working costs go down. 

 But there is no reason why far richer deposits — workable at any 

 locality — should not be discovered. 



Mineral, Industry in Rhodesia.— Air. j. P. 



Johnson's book, mentioned on a previous page (see p. ii6j, is 

 intended to be a guide to the present position and future possi- 

 bilities of the mineral industry of Rliodesia. After an intro- 

 ductory chapter in which the author gives a rapid glance at the 

 geology of the country, he pa.s.ses on to review the conditions 

 under which gold is now being mined there, and very briefly de- 

 scribes nearly thirty Rhodesian gold-mining properties. Idie 

 T910 output had a sterling v.due of over 2| million pounds. A 

 chapter is then devoted to th.e small mine industry, and the in- 

 creasing prominence of other metals is next dealt with. At 

 ])rcsent chromium is one of the most important of these, but 

 reference is also made to tungsten, thorium, tantalum, uranium, 

 nickel, cobalt, copi^er, lead, zinc, vanadium, cadmium, mercury, 

 tin and silver. The total output of silver to date is estimated 

 to amount in value to £134,000. Chapter 5 is devoted to a con- 

 sideration of South African tin deposits other than those in 

 Rhodesia, special attention being given to the Potgietersrust and 

 Rooiberg tin iields. Mention is made of a few small occur- 

 rences of tin in the Transvaal, and the chapter closes with a 

 short account of the occurrences of tin near Cape Town on the 

 farms W'elbeloond, Langverwacht, and others adjacent thereto. 

 Amongst non-metalliferous minerals, the chief position is given 

 to asbestos, the others treated of being mica, magnesite, talc, 

 graphite, and barite. Diamonds and coal haye a chapter to 

 themselves ,and it is recorded that the ^^'ankie mine has hitherto 

 yielded over 900,000 tons of coal, of which 180.000 represented 

 the 1910 output. The Rhodesian yield of diamonds, mainly 

 derived from the Roberts A'ittor occurrence, has aggregated over 

 £30,000 in value, together with about £8,000 in other precious 

 stones. The final chapter of the book consists of hints to pros- 

 pectors. 



