152 rRECIOUS STONES. 



Chab'asite. — A precious stone, white, and sometimes trans- 

 ])aivnt ; a kind of zeolite. 



Chalcedony. — An uncrystallizcd variety of quartz. It is 

 usually of a grayish color, but sometimes occurs milky- 

 white, pinkish, or of a smalt-blue; in the latter case it is 

 called sftpphh'iue. 



Chalced'onyx. — A variety of chalcedony, having alternate 

 stripes of white and gray. 



Chrys'oberyl. — A yellowish-green gem, next to .sapphire in 

 " liardness, consisting of alumina and the earth glucina. 

 On account of a peculiar opalescence presented by the 

 crystals, the mineral has been called cymoplunie. 



Chrys'olite. — A mineral of a greenish hue, often transparent. 

 It is sometimes granular, and at other times occurs in 

 small crystals. 



Chrys'oprase. — A chalcedonic variety of quartz. Its color is 

 commonly apple-green, and often extremely beautiful. It 

 is translucent, or sometimes semi-transparent. 



Col'oplionite. — A variety of garnet, of a reddish-yellow or 

 brown color, occurring in small amorphous granular masses. 



Di'amond. — The most valuable and hardest of gems. When 

 pure it is perfectly clear and pellucid, and is eminently 

 distinguished from all other substances by its vivid splen- 

 dor and the brightness of its reflections. 



Em'erald. — A gem of a beautiful green color, somewhat harder 

 than quartz ; it occurs in prisms with a regular hexagonal 

 base, and ranks next in value to the Oriental ruby and 

 sapphire. It consists chiefly of glucina, with silica, alu- 

 mina, a very little lime and iron. 



Eu'clase. — A very rare mineral, of a pale-blue or green color. 

 A species of emerald. 



Gar'net. — A mineral or gem of which there are several vari- 

 eties, mostly crystallized, and of a reddish color. It is a 

 silicate of alumina with oxide of iron. 



Jas'per. — A genus of stones of the silicious class. It is very 

 comj^act, is found of various colors, — dark green, red, brown, 

 yellow, grayish, and sometimes bluish and black, — and 

 emulates the appearance of the finer marbles or semi- 

 pellucid gems. 



Mesom'elas. — A precious stone, with a black vein parting 

 eveiy color in the midst. 



O'nyx. — A species of agate, stratified with opaque and trans- 



