THE ORIGIN OF DIAMONDS 25 



Gigantic as the Cullinan diamond is, it represents 

 only about half the daily output of the De Beers mines. 

 By the end of 1904 ten tons of diamonds, valued at 

 =60,000,000 sterling, had been removed from the 

 Kimberley mines. It is difficult to imagine what has 

 become of them all, and since they are, unlike paste, 

 durable and permanent, how the demand for additions 

 to those in use, keeps up. Twelve years ago about four 

 million pounds was spent annually by the public on the 

 purchase of diamonds. It is stated that the annual 

 demand and expenditure are now even larger. 



Diamond is a peculiar form or variety of the chemical 

 element carbon a very peculiar form most people will 

 say who remember that charcoal and lamp-black are the 

 common form of carbon. That one and the same 

 unchangeable chemical element can exist as an 

 amorphous black lump or powder, and also without 

 addition or loss of chemical constituents, as the clearest, 

 hardest, and most brilliant of crystals, is a paradox. 

 The same strange capacity for existing in two totally 

 different forms is exhibited by other fairly familiar 

 elements. Sulphur is found in tertiary water-deposited 

 clays in Sicily (it has nothing to do with Etna or 

 Vesuvius) in the form of clear, lemon-coloured crystals 

 half an inch or more in length. If you take some 

 commercial stick-sulphur and melt it in a porcelain 

 spoon, and pour half the melted stuff like treacle into a 

 jar of water, you will find that it cools as translucent 

 threads which are pliable and soft. The other half 

 which you leave in the spoon to cool shoots out into the 

 form of long brittle crystals of a needle-like shape. 

 These two varieties of sulphur are nearly as different as 

 lamp-black and diamond. 



Diamonds are found at the Cape in a " blue ground " 

 which is of volcanic origin, formed by the action of 

 steam under enormous pressure. The blue volcanic 

 mud has been thrust up from great depths in the earth's 



