INGENUITY AND LUXURY 



of chromium salts placed in the original mixture, and 

 partly by the degree of heat employed. But the one 

 great difficulty about the shape of the crystals long 

 proved insuperable. It was finally met, however, 

 through the ingenuity of M. Verneuil, a Frenchman 

 already well known for his experiments in this field, 

 who devised a method by which the alumina powder 

 prepared originally from a solution of common 

 alum is sifted down a tube through an oxy-hydrogen 

 flame and, thus fused, is deposited drop by drop, or 

 more properly as a spray, on a fixed point below the 

 flame, where it builds up a pear-shaped crystal pre- 

 cisely as stalagmites are built up by dripping water 

 in a cave. Unfortunately the gem thus formed breaks 

 into fragments when touched; but the fragments are 

 still of marketable size ; and true rubies and sapphires 

 thus manufactured have now entered the field of com- 

 merce. 



Rubies and sapphires so formed duplicate absolutely 

 the desirable qualities of the natural gems; and their 

 production must obviously affect the market value of 

 these gems, as well as the mining industry through 

 which they are obtained. The public should be 

 warned, however, against accepting as "true artifi- 

 cial " rubies, emeralds, and sapphires, the numberless 

 glass imitations that will continue to flood the market 

 so long as these jewels retain their popularity. 



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