THE CULLINAN DIAMOND.— A DESCRIPTION OF THE 

 BIG DIAMOND RECENTLY FOUND IN THE PREMIER 

 MINE, TRANSVAAL." 



By F. II. Hatch, Ph. D., F. G. S., and G. S. Corstorphine, Ph. D., F. G. S. 



Great interest has been excited, not onh^ in the Transvaal, but 

 tliroiig-hont the worhl, by the discovery at the Premier mine, on Wed- 

 nesday, the 25th of January, 1905, of the hirgest diamond hitlierto 

 known. The stone was found by Mr. "Wells, surface manager, in the 

 yellow ground about 18 feet from the surface, a brilliant flash of light 

 from a projecting corner having caught his attention. After a pre- 

 liminary cleaning it weighs 8,02-lf carats. According to Gardner 

 Williams the South African carat is eqiuvalent to 3 "iTi grains ; con- 

 sequently the diamond weighs 0,000 '5 grains troy, or 1 "ST pounds 

 avoirdupois. Through the courtesy of the directors of the company, 

 we have been enabled to make an examination of the stone, with the 

 following result : Roughly speaking, it measures 4 by 2| by 2 inches ; 

 but its size and shape will be best realized by reference to the photo- 

 graphs reproduced on Plates I and II. which represent the diamond 

 from four dift'erent points of view and its actual size. These beauti- 

 ful photographs were taken by Mr. E. H. V. Melvill for the i3urposes 

 of this description. The stone is bounded by eight surfaces, four of 

 which are faces of the original crystal, and will be referred to in this 

 descrij^tion under the letters A, B, C, D, and four are cleavage sur- 

 faces, the cleavage being of course parallel to the face of the octahe- 

 dron. In the following description these cleavage surfaces are re- 

 ferred to under the letters E, F, G, H. They are distinguished from 

 the original octahedral faces by greater regularity and smoothness. 

 The shape and relative position of these various surfaces can be seen 

 in the diagrammatic projection depicted in the text figure, which 

 has been drawn in the mineralogical laboratory of the Oxford Uni- 

 versity Museum, by the kind permission of Professor Miers, F. R, S. 

 The drawing is to half scale. 



a Reprinted by permission from the Geological Magazine (London), Decade V, 

 Vol. II, No. 490, April, 1905. 



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