THE DIAMOND INDUSTRY AT KIMBERLEY. 459 



moisture soon have a wonderful effect upon it. Large pieces 

 which were as hard as ordinary sandstone when taken from the 

 mine, soon commence to crumble. At this stage of the work, the 

 winning of the diamonds assumes more the nature of farming 

 than of mining ; the ground is continually harrowed to assist pul- 

 verization by exposing the larger pieces to the action of the sun 

 and rain. The blue ground from Kimberley mine becomes quite 

 well pulverized in three months, while that from De Beers re- 

 quires double that time. The longer the ground remains exposed, 

 the better it is for washing." * The process of exposure being 

 completed, the blue ground is then carried to very large, elabo- 

 rate, and costly washing machines, in which, by means of the 

 action of running water, the diamonds are separated from the 

 ordinary earth. It may be mentioned that in this process one 

 hundred loads of blue ground are concentrated into one load of 

 diamondiferous stuff. Another machine, the "pulsator," then 

 separates this latter stuff, which appears to be a mass of blue and 

 dark pebbles of all shapes, into four different sizes, which then 

 pass on to the assorters. " The assorting is done on tables, first 

 while wet by white men, and then dry by natives." f The assorters 

 work with a kind of trowel, and their accuracy in detecting and 

 separating the diamond from the eight different kinds of mineral 

 formations which reach them is almost unerring. " The diamond 

 occurs in all shades of color from deep yellow to a blue white, 

 from deep brown to light brown, and in a great variety of colors, 

 green, blue, pink, brown, yellow, orange, pure white, and opaque." J 

 The most valuable are the pure white and the deep orange. " The 

 stones vary in size from that of a pin's head upward ; the largest 

 diamond yet found weighed 428^ carats. It was cut and exhibited 

 at the Paris Exhibition, and after cutting weighed 228i carats. 

 " After assorting, the diamonds are sent daily to the general office 

 under an armed escort and delivered to the valuators in charge of 

 the diamond department. The first operation is to clean the dia- 

 monds of any extraneous matter by boiling them in a mixture of 

 nitric and sulphuric acids. When cleaned they are carefully 

 assorted again in respect of size, color, and purity." * The room 

 in the De Beers office where they are then displayed offers a most 

 striking sight. It is lighted by large windows, underneath which 

 runs a broad counter covered with white sheets of paper, on 

 which are laid out innumerable glistening heaps of precious 

 stones of indescribable variety. In this room are concentrated 

 some 60,000 carats, the daily production of the Consolidated Mine 

 being about 5,500 carats. " When the diamonds have been valued 

 they are sold in parcels to local buyers, who represent the leading 



* Report, 1890, General Manager, De Beers. f Ibid. \ Ibid. * Ibid. 



