COMPOUNDS OF ALUMINUM. 193 



Varieties. The name sapphire is usually restricted, in 

 common language, to clear crystals of bright colors, used as 

 gems ; while dull, dingy-colored crystals and masses are 

 called corundum, and the granular variety of bluish-gray 

 and blackish colors containing much disseminated magne- 

 tite (whence its dark color) is called emery. 



Blue is the true sapphire color. When of other bright 

 tints, it receives other names ; as oriental ruby, when red ; 

 oriental topaz, when yellow ; oriental emerald, when green ; 

 oriental amethyst, when violet, and adamantine spar, when 

 hair-brown. Crystals with a radiate chatoyant interior are 

 often very beautiful, and are called asteria, or asteriated 

 sapphire. 



Diff. Distinguished readily by its hardness, exceeding all 

 species except the diamond, and scratching quartz crystals 

 with great facility. 



Obs. The sapphire is often found loose in the soil. Meta- 

 morphic rocks, especially gneissoid mica schist, and granu- 

 lar limestone, appear to be its usual matrix. It is met with 

 in several localities in the United States, but seldom suffi- 

 ciently fine for a gem. A blue variety occurs at Newton, 

 N. J., in crystals sometimes several inches long ; bluish and 

 pink, at Warwick, X. Y.; white, blue, and reddish crystals 

 at Amity, X. Y. ; grayish, in large crystals, in Delaware 

 and Chester counties, Pennsylvania ; pale blue crystals 

 have been found in bowlders at West Farms and Litchfield, 

 Conn. It occurs also in large quantities in North Carolina, 

 where crystals are numerous though rarely fit for jewelry, 

 and where one has been obtained weighing 312 pounds, and 

 having a reddish color outside and bluish-gray within ; also 

 in Cherokee County, Georgia ; in Los Angeles County, Cali- 

 fornia. Emery is mined at Chester, in Mass. 



The principal foreign localities are as follows : blue, from 

 Ceylon ; the finest red from the Capelan Mountains in the 

 kingdom of Ava, and smaller crystals from Saxony, Bohemia 

 and Auvergne ; corundum, from the Carnatic, on the Mala- 

 bar coast, and elsewhere in the East Indies ; adamantine 

 spar, from the Malabar coast ; emery, in large bowlders 

 from near Smyrna, and also at Naxos and several of the 

 Grecian islands. 



The name sapphire is from the Greek word sappheiros, 

 the name of a blue gem. It is doubted whether it included 

 the sapphire of the present day. 



