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Marvels of the Universe 



which was once noted for its pearls, though of Jate thej' have greatly decreased in commercial 

 importance, as they are of no great size and have a dull, lifeless sheen which is comparable to 

 that of glazed porcelain. 



Pliny relates that a red-coloured pearl was in his day taken from a shell named Myes, which 

 inhabited the Thracian Bosphorus. Another shell in which pearls have been found is the hammer- 

 headed oyster, but such specimens are prized more on account of their rarity than for any peculiar 

 qualit}^ of the gem itself. The common edible mussel and some species of the wedge shells must 

 also be added to the list of pearl-bearers. These names are necessarily taken as representative of 

 certain families, many members of which are to be found throughout the world, all bearing the same 

 specific quality of pearl production. For instance, the river-mussels of England and Sweden have 





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nolo bu'j [H'. SMiUe Kent. 



PEARLS 

 A photograpn showing the several varieties of pearls. In the higher part of the picture are more or less perfect pearls, 

 amongst which, however, can be seen several "baroque" pearls. To the left are pearls immersed in a nacreous matrix, while 

 at the bottom of the picture are simole " blister " pearls 



their counterpart in those of Ameiica, which are often furnished with a nacre of great depth and 

 beauty and sometimes contain excellent peai'ls. 



A variety of colours are to be found in pearls — some are dull white, like those of the English 

 rivers: many shells bear pink pearls: while uncommon shades, such as apricot, green, deep rose, 

 purple and black are sometimes found. There was in the famous Hope collection a pearl found in 

 American waters, which glowed with the fierv colours of the opal, tempered with that soft lustre 

 which is the pecuhar attribute of this gem. ;\Ir. Sa^•ille Kent mentions in his book, " The Naturalist 

 in Australia," the finding of several pearls the colour of gold, and a case was brought before the notice 

 of the writer of a man who possessed a set of studs headed with pearls that could not easily be 

 distinguished from solid gold. But the pearls of greatest beauty and renown are those taken in 

 the fisheries of the Persian Gulf or Ceylon. They are of the true Orient variety — creamj-, mellow 

 and lustrous. This lustre results, not from any peculiar quality of the nacre, but from the slightly 

 uneven surface of each coating, which causes the globule to catch and diffuse the light. To what 

 circumstances the coloration of pearls is due is a question not 3'et completely settled, though the 

 most acceptable theory ascribes the phenomenon to some mineral substance held in solution in 



