2 INTRODUCTION 



besides their intrinsic beauty they possess the added charm of rarity. This latter character 

 is perhaps the one to which is most largely due the costliness of these objects, for the 

 possession of something rare, something that it is impossible for every other person to 

 possess, has ever exercised a fascination upon human nature. 



The minerals which combine the highest degrees of beauty, hardness, durability, and 

 rarity — diamond, ruby, sapphire, and emerald, for example — are by common consent placed 

 in the foremost rank of gems ; those in which these characters, especially that of hardness, 

 are less conspicuous, are less highly esteemed. The former may be grouped together as 

 precious stones, while the latter, characterised sometimes by greater beauty, but by lower 

 hardness and more common occurrence, are known as semi-precious stones. 



It is impossible to draw a hard and fast line between precious and semi-precious stones ; 

 a stone which one person might regard as precious, another would place with semi-precious 

 stones. In deciding the point, not one character but all must be taken into consideration, 

 and the rarity or commonness of the stone set against its other characters. Thus the 

 emerald, though comparatively soft, is one of the costliest of stones owing to its magnificent 

 colour, and the rarity of faultless specimens. Again, precious opal and turquoise, though 

 opaque and comparatively soft, are more valuable than is amethyst, which, though 

 transparent and harder, is yet, on account of its commonness, regarded as only a semi- 

 precious stone. 



Just as the essential characters of a gem are developed in different minerals to different 

 degrees, so do these characters differ in degree in different specimens of the same mineral 

 species. The hardness is in all cases the same in the same species, but the transparency 

 and colour may be very different in different specimens, so that while some furnish us with 

 the finest examples of precious stones, others may be entirely unsuitable for ornamental 

 purposes, and the remainder furnish stones of inferior quality. Thus the mineral species 

 beryl includes not only the costly emerald, but also the far less beautiful and less valuable 

 golden beryl and pale greenish-blue aquamarine, and the cloudy and opaque common beryl, 

 which is destitute of the essentials of a gem, and is therefore never used as such. The 

 transparent varieties of minerals used as precious stones are distinguished by the prefix 

 " precious " from the opaque or " common " varieties. 



The value of a mineral as a gem does not depend solely upon its natural characters, but 

 is influenced to a very large extent by the fashion of the day. A stone which at one time 

 commands a high price, at another, for no apparent reason, will scarcely find a purchaser ; 

 while minerals, at first comparatively unknown to the jeweller, will leap suddenly into 

 popular favour. At one time diamonds are most in favour, at another the so-called fancy 

 stones. At the present time the latter is the case ; scarcely more than a dozen years ago 

 the jeweller's stock consisted of diamonds, rubies, sapphires, emeralds, and garnets, with 

 an occasional topaz or aquamarine. Now almost all the stones described in this book, 

 a list of which will be found in the table of contents, and most of which are coloured, are 

 commonly bought and sold in the precious stone market. Many of the minerals now cut as 

 gems are not suitable in every respect for the purpose, and this is specially so in the case of 

 those minerals which are cut and worn more for the association of the wearer with the place 

 of their occurrence than for their intrinsic beauty or suitability. 



The minerals which must be reckoned as precious stones are by no means fixed in 

 number, nor is it a fact that a mineral once used as an ornamental stone is ever after used 

 as such. New minerals come into favour and old ones fall out of use, but a certain number, 

 the richest and most beautiful of gems, survive all the changes and chances of fashion, and 

 stand now, where they did ages ago, highest of all in popular esteem. 



