72i 



DIAMOND. 



Diamond. 



2. Colour. 



S. Trans- 

 parency. 



4. Free, 

 dom from 

 flaws, 

 veins, and 

 stains 



diamonds exceeds that given in the table ; but for a 

 stone that is flawed, cloudy, or of a bad colour, some- 

 times three quarters of the whole value may be deduct- 

 ed. 



The most frequent colours of the diamond, as al- 

 ready mentioned, are the white and grey, and of these 

 the most highly prized by the jeweller is the snow 

 white. The brown varieties are of inferior value, and 

 the yellow diamond, which is not uncommon, is only 

 esteemed of equal value with the snow white variety 

 when the colour is deep and pure. The other varieties 

 of colour occur but rarely, and are viewed as objects of 

 curiosity to the collector rather than as generally in- 

 teresting to the jeweller. Thus a rose diamond is more 

 valuable than a snow white diamond of equal weight, 

 owing to the great beauty of its colour, and its rarity ; 

 the green diamond is much esteemed on account of its 

 colour, but the blue diamond is only prized for its 

 rarity, as the colour is seldom pure. The black dia- 

 mond, which is uncommonly rare, and destitute of 

 beauty, is very highly prized by collectors. * 



A good diamond must be nearly completely transpa- 

 rent. If semitransparent, it is of little value. Transpa- 

 rency and purity comprehend what is called the water 

 of the diamond by jewellers. If the gem is transparent 

 and quite pure, it is said to be of the first water ; if less 

 transparent and pure, of the second, or of the third 

 water. 



Diamonds in a state of nature are sometimes rent in 

 different directions ; these rents are either confined to 

 the surface or central parts of the stone, or traverse its 

 whole mass. When the rents traverse the whole mass 

 of the stone, or traverse its interior, the value of the 

 diamond is diminished one half. If the rents are su- 

 perficial, the value of the stone is not very greatly di- 

 minished. It requires a very experienced eye to dis- 

 tinguish these different kinds of refits. 



Rough diamonds are frequently beamy, that is, look 

 fair to the eye, yet are so full of veins to the centre 

 that no art or labour can polish them. Mr Milburn, 

 in his valuable work on Oriental Commerce:, vol. ii. p. 80, 

 gives the following account of heamy diamonds. " The 

 veins run through several parts of the stone, and some- 

 times through all ; and when they appear on the out- 

 side, they shew themselves like protuberant excres- 

 cences, from whence run innumerable small veins, ob- 

 liquely crossing one another, and shooting into the 

 body of the stone. The stone itself will have a bright 



and shining coat, and the veins will look like very small 

 veins of polished steel rising upon the surface of the 

 stone. This sort of stone will bear no polishing, and 

 is scarcely worth a rupee per mangalin. Sometimes 

 the knot of the veins will be in the centre, the fibres 

 will shoot outward, and the small ends terminate in 

 the coat of the diamond. This is more difficult to dis- 

 cover, and must be examined by a nice eye ; yet you 

 may be able here and there to observe a small protu- 

 berance, like the point of a needle, lifting up a part of 

 the coat of the stone ; and though by a great deal of 

 labour it should be polished, it will be a great charge, 

 and scarcely pay for the cutting, and is therefore to be 

 esteemed as little better than the former. But if you 

 are not very careful, they will throw one of these stones 

 into a parcel, and oftentimes the largest." 



A good diamond should never contain small spots of 

 a white or grey colour of a nebulous form ; it should be 

 free of small reddish and brownish grains, that some- 

 times occur on their surface, or in their interior. 



A good diamond should split readily in the direction 

 of the cleavage ; it sometimes happens, however, that the 

 folia are curved, as is the case in twin crystals. When 

 this is the case, the stone does not readily cut and po- 

 lish, and is therefore of inferior value. 



In the cut and polished gem, the thickness must al- 

 ways bear a certain proportion to the breadth. It must 

 not be too thin nor too thick ; when too thin it loses 

 much of its fire, and appears not unlike glass. 



If these are not properly disposed, the diamond loses 

 much of its fire, and its value is thereby diminished. 



The only diamond districts at present known, are 

 those of India, Borneo, and Brazil. In the earlier agesy 

 all the diamonds of commerce were obtained from In- 

 dia, but now the diamond mines of that country have 

 become comparatively inconsiderable ; several of them 

 have been abandoned, and scarcely any of the rest con- 

 tribute to the supply of the European market. Borneo 

 furnishes annually a small quantity. The diamonds of 

 the East are imported into Europe in their rough state, 

 in small parcels, called bulses, neatly secured in linen, 

 and sealed by the merchant, and are generally sold in 

 Europe by the invoice, that is, are bought before they 

 are opened, it being always found they contain the va- 

 lue for which they were sold in India, and the pur- 

 chaser gives the importer such an advance on the in- 

 voice as the state of the market warrants. The bulse 

 contains stones of various shapes and sizes. They may 



Diamond- 



5. Reeula- 

 rity of the 

 cleavage. 



6. Propor- 

 tion ot 

 parts. 



7. Tlie set- 

 ting on of 

 the facets. 



Diamond 

 trade. 



* Mr Milburn has the following observations on the colour of rough diamonds, which are deserving the attention of the diamond 

 merchant. " The colour should be perfectly crystalline, resembling a drop of clear spring water, in the middle of which you will per- 

 ceive a strong light, playing with a great deal of spirit. If the coat be smooth and bright, with a little tincture of green in it, it is 

 not the worse, and seldom proves bad ; but if there is a mixture of yellow with green, then beware of it, — it is a soft greasy stone, 

 and will prove bad. 



If the stone has a rough coat, so that you can hardly see through it, and the coat be white and look as if it were rough by art, and 

 clear of flaws or veins, and no blemish cast in the body of the stone (which may be discovered by holding it against the light,) the 

 stone will prove good. 



It often happens, that a stone will appear of a reddish hue on the outward coat, not unlike the colour of rusty iron ; yet by look- 

 ing through it against the light, you may observe the heart of the stone to be white, (and if there be any black spots or flaws, or 

 veins in it, they may be discovered by a true eye, although the coat of the stone be the same,) and such stones are generally good 

 and clear. 



If a diamond appears of a greenish bright coat, resembling a piece of green glass, inclining to black, it generally proves hard, and 

 seldom bad ; such stones have been known to have been of the first water, and seldom worse than the second ; but if any tincture of 

 yellow seem to be mixed with it, you may depend upon its being a very bad stone. 



All stones of a milky coat, whether the coat be bright or dull, if never so little inclining to a bluish cast, are naturally soft, and in 

 danger of being flawed in the cutting; and though they should have the good fortune to escape, yet they will prove dead and milky, 

 and turn to no account. 



All diamonds of cinnamon colour are dubious ; but if of a bright coat, mixed with a little green, then they are certainly bad, and 

 are accounted amongst the worst of colours. 



You will meet with a great many diamonds of a rough cinnamon coloured coat, opaque, ; this sort is generally very hard, and when 

 cut, contains a great deal of life and spirit ; but the colour is very uncertain; it is sometimes white, sometimes brown, and some- 

 times of a fine yellow." 



