494 Sir J. B. Stone — The Kimherley Diamond Mines. 



Ground are necessarily avoided, as it might damage the imbedded 

 diamonds. Therefore weathering action alone is relied upon, subject 

 to the mass being turned over occasionally by "harrowing" it. 



The "depositing floors" cover vast areas extending to many 

 square miles of country, which are carefully protected by fences, 

 and the whole vigilantly guarded. The reducing process takes, not 

 merely days or months, but years to bring the material into a con- 

 dition ready for the work of washing and sorting. At the present 

 time there is a valuable reserve, the worth of which must amount 

 to many years' income ; in other words, there are many millions of 

 pounds worth of diamonds stored in these disintegrating areas.^ 



It is not to the purpose here to refer particularly to tbe process of 

 washing and sorting, or to the thousand and one interesting details 

 that form part of the story of the gigantic and rich enterprises of 

 Kimberley, among which the energy of the De Beers Company takes 

 such a conspicuously leading part, but it is more pertinent to follow 

 the material itself through the series of operations which lead to 

 the final results, and to glean useful geological facts respecting its 

 composition and the history of the diamonds. 



The first process of washing carries away all the finer particles 

 of mud, permits the picking out of larger " stones," of easily 

 recognized volcanic rock, or of similar substances, and leaves 

 a mass of granular material from the size of a pin's head to that of 

 a small apple, the several substances amongst it being well and 

 distinctly separated. This is now turned over to the sorters, who 

 proceed to riddle it into classified heaps. Those consisting of the 

 greater particles, amongst which the larger and more valuable stones 

 may be expected to be found, ai'e placed in the hands of confidential 

 and responsible Europeans ; the finest, from which the most minute 

 diamonds are extracted, being examined by Kaffirs (all of whom 

 are carefully watched), who go over the fine refuse almost grain 

 by grain. 



These granular masses in process of sorting are highly interesting. 

 They are rich in garnets, in olivine, in pyrites, and many other 

 minerals ; and they disclose the detailed composition of the breccia 

 of the "Blue Clay." 



Among this composite material the diamonds are found in the 

 proportion of about 1 to IJ carats to the ton, and in size, from the 

 smallest grain to " stones " of the greatest value.^ 



A parcel of diamonds in the rough (such as, for instance, the 

 day's product of one of the mines) is an extremely interesting 

 subject of investigation and study. Such a bowl full of stones, 

 amounting to thousands of pounds in value, fresh from the 

 cleaning process of having been boiled in acids, present in their 

 uncut and unassorted condition a general resemblance to a handful 



^ A better idea of the riclies of the mines will be gleaned from the brief statement 

 which has just publicly appeared (July, 1895), that the De Beers Company have 

 sold the output for the year for the sum of three million and a half pounds sterling. 



■^ One in the possession of the De Beers Company weighed in the rough state as 

 much as 428 carats. 



