348 THE DIAMOND AND OTHER PRECIOUS STONES. 



and tlie manufacture of tlio diamond. Although this result might not 

 be advantageous to commerce, it ;vould be so to science. Nowhere does 

 nature show us the diamond in the locality where it has been formed ; it 

 is now only obtained from ground which has changed its place, so that 

 we get no light on the primitive conditions of its crystallization, a cir- 

 cumstance which seems to conUrm the views of Despretz, which is, that 

 in Brazil, side by side with the diamond, there occurs a curious substance 

 as hard as the diamond, which is called by the Portuguese carbonado, and 

 in trade at Paris carhonc. Speaking of the mines of Brazil, Tennant 

 says of it : "There is found here a considerable quantity of a black sub 

 stance of the same specific gravity as the diamond, laminated or rather 

 composed of a succession of laminella generally broken into separate 

 fragments. It is too imperfectly crystallized to be cut ; though it pos 

 sesses in places the brilliance of the diamond, and can be reduced t(- 

 powder for the polishing of other stones. Its name, carbonado, is due to 

 its having an appearance resembling charcoal. May not this be the 

 same substance as that artificially obtained by Despretz '? In the age 

 of Louis XIV, it was thought that it was quite possible to increase the 

 size of diamonds by placing them in certain solutions, just as a piece of 

 salt may be increased in size by placing it in a solution of the same 

 substance. Despretz has, doubtless, considered the property that a 

 crystal possesses of attracting and regularly arranging around itself 

 l)articles of matter analogous to its own. At present this is the whole 

 scientific condition of the subject. Let us wait for future developments. 



Several years ago the premature announcement of the artificial pro- 

 duction of diamonds agitated all Paris. Baron Thtnard, however, by 

 an experimental examination reassured tlie many merchants and families 

 who had been alarmed on account of the threatened depreciation of their 

 fortunes, based on the value of this queen of gems. Since this time the 

 number of diamonds has increased in France, and is every day increasing, 

 even more rapidly than in England, and now represents an immense 

 capital. According to the reniark of Achard, there is no article which 

 being resold, suflers so little loss, so little depreciation, while at the same 

 time it is always in demand. It may almost be considered a circulating 

 medium for high values. Furthermore, in the actual state of physics 

 and chemistry, nothing Avarrants the fear that the artificial will ever 

 compete vrith the natural product. The case is analogous to the well- 

 known j>roduction of the gold pieces made by M. Sage, from gold ex- 

 tracted from the ashes of certain burned vegetable substances, a beautiful 

 scientific result, but by no means lucrative, since every piece of twenty 

 francs cost 125 francs in the making. 



In like manner, we may say that if the process were known, the arti- 

 ficial geni would cost more than its worth. 



The other precious stones have been designated " colored gems.'' In 

 fact, their principal merit is the beauty of color and play of light which 

 distinguishes them, but to this we nuiy add hardness, which insures their 



