INGENUITY AND LUXURY 



We have not space here for consideration individually 

 of each of the principal precious stones, but in another 

 place will be found tables giving the composition, 

 location, and characteristics, etc., of the more impor- 

 tant. The subject of artificial gems and imitation 

 gems will be considered in a moment. But before 

 beginning this subject of growing importance, a word 

 should be said as to the methods employed by unscrupu- 

 lous gem dealers of using thin layers of true gem stones, 

 in connection with colored glass, as a veneer for making 

 what appear to be very good gems. These are made 

 in two forms, and are known to the trade as " doub- 

 lets" and " triplets," respectively. Doublets are made 

 by cementing a thin piece of some gem stone over a 

 paste, or glass, backing of the same color, so that the 

 top of the stone above the setting responds to the tests 

 of the real gem. By testing the under side of the stone 

 the fraud is revealed. Triplets are made by placing 

 thin layers of a gem stone both front and back of 

 the paste, so that the glass is sandwiched in between, 

 and can only be detected at the edges, which are usually 

 carefully covered by the setting. 



It is possible to alter the color of certain stones by 

 the careful application of heat, the process being known 

 technically as " pinking," or " burning." This is a 

 perfectly legitimate process, however, and enables 

 the jeweler to convert certain topazes, for example, 

 into gems of coveted pink color. Pink topazes 

 occur very rarely in Nature; but as they are seen very 

 frequently on the market it may be taken for granted 

 that most of those offered in the shops have been 



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