82 CARBON. 



Diamonds with few exceptions are obtained from alluvial 

 washings* In Brazil, the sands and pebbles of the diamond 

 rivers and brooks (the waters of which are drawn off in the 

 dry season to allow of the work) are collected and washed 

 under a shed, by a stream of water passing through a suc- 

 cession of boxes. A negro washer stands by each box, and 

 inspectors are stationed at intervals. When a diamond is 

 found weighing 17^ carats, the negro is entitled to his 

 liberty. 



The largest diamond of which we have any knowledge is 

 mentioned by Travernier, as in the possession of the Great 

 Mogul. ' It weighed originally 900 carats, or 2769'3 grains, 

 but was reduced by cutting to 861 grains. It has the form 

 and size of half of a hen's egg. It was found in 1550", in the 

 mine of "Colone. The diamond which formed the eye of a 

 Braminican idol, and was purchased by the Empress Catha- 

 rine II. of Russia from a French grenadier who had stolen 

 it, weighs 193 carats, and is as large as a pigeon's egg. 

 The Pitt or regent diamond is of less size, it weighing but 

 136*25 carats, or 419^ grains; but on account of its un- 

 blemished transparency and color, it is considered the most 

 splendid of Indian diamonds. It was sold to the Duke of 

 Orleans by Mr. Pitt, an English gentleman, who was gover- 

 nor of Bencolen, in Sumatra, for £130,000. It is cut in the 

 form of a brilliant, and is estimated at £125,000. The Rajah 

 of Mattan has in his possession a diamond from Borneo, 

 weighing 367 carats. The Koh-i-noor, on its arrival in 

 England, weighed 186.016 carats. It has since been re-cut 

 and reduced one third in weight. 



The diamonds of Brazil are seldom large. Maure men- 

 tions one of 120 carats, but they rarely exceed 18 or 20. 

 One weighing 254f carats, called the "Star of the South" 

 was found in 1854. It will be reduced one-half in cutting. 



Diamonds are valued according to their color, transpa- 

 rency and size. When limpid (of pure water) and no ex- 

 traordinary magnitude, the value of a wrought diamond is 

 estimated by first ascertaining the weight in carats. * The 



How are diamonds obtained ? How are diamonds valued 1 



* A carat is a conventional weight, and is divided into 4 grains, 



which are a little lighter than 4 grains troy ; 74 1-16 carat grains are 



qual to 72 troy grains. The term carat is derived from the name of 



bean in Africa, which, in a dried state, has long been used in that 

 country for weighing gold. These beans were early carried to India 

 and were employed there for weighing diamonds. 



