Baroness Burdett-Coutts has supplemented this by the addition of money prize. 

 and has offered to contribute the further sum of £50 for prizes in the year 1876 



It is estimated that the value of the diamonds found at the Cape from March 

 1867, to the present time, exceeds twelve millions of pounds sterling. 



I am enabled to exhibit not only a large collection of these diamonds, bu 

 also samples of the natural materials found associated, with them.^ In November 

 1873, one of my former students brought me the specimen from South Africa 

 which in its original state weighed 112 carats ; it has since been cut by a London 

 diamond-cutter into the beautiful brilliant represented by Figs. 1, 2, 3, weighino 

 66 carats. The stone has a delicate yellow tinge, and exceeds in size and 

 hrilliancy any diamond in the British Crown. 



Fig. 1.— Front View. 



Fig. 2.— Side View. 



Ftg. 3,— Back View. 



Fig. 4.- Side. 



" Star of South Africa." 



Exact size, 46i carats. 



In its rougli state, 83 carats. 



Fig. 5.— Face. 



Fig. 6.— Back. 



Figs. 4, 5, 6, represent a South African diamond in the possession of Lod 

 Dudley, valued at £20,000. 



It may be remarked, with regard to this class of gem-cutting, that 200 year 

 since the English diamond-cutters were the most celebrated in the world. Th 

 diamond-rutting trade is now being restored to England, and the stone (Figj 

 1, 2, 3) affords a fair sample of the excellent work that can now be done here, 

 may mention that the stone in its present form is worth £10,000, whilst the value c 

 the models of it, which have been cut by the best lapidaries, is a mere trifle 

 that in glass costing only 10s., and that in crystal only £2. The rule given b; 

 Jeffries and the best authorities upon diamonds for ascertaining the value of cu 

 diamonds, is to multiply the square of the weight in carats by eight, and call i 

 pounds, so that this diamond would, according to this computatioc, be wort] 

 66 X 66 X 8 = £34,848. The weight of the Koh-i-noor is 102i carats, whicl 

 valued according to the same rule (102 x 102 x 8) would amount to £83,232 



. ^ Professor Tennant exhibited a South African diamond in the matrix (consisting chief! 

 of broken fragments of chloritic and clay-slates), likewise some interesting photographs of th 

 Diamond-workings in South Africa. 



