ELISHA MITCHELL SCIENTIFIC SOCIETY. 75 



These zircons occur in crystalline rocks, especially in 

 granular limestone, in chloritic and other schists, in gneiss, 

 syenite, and also in granite and sometimes in iron ore 

 beds. Zircon syenite is a coarse syenitic rock containing 

 crystals of zircon along with oligoclase, aegirine, claeolite 

 and epidote. 



Crystals of zircon are common in most auriferous sands 

 and sometimes are found in volcanic rocks. 



In Ceylon they are mainly found in the alluvial sands. 

 In the Ural Mountains mainly in the gold regions. In 

 Norway sometimes in syenite, sometimes in the iron mines. 

 Zircons are also found in Transylvania, in Bohemia, in 

 Saxony and in the Tyrol. 



The occurrence at Expailly, near Le Puy, in France is 

 well known and of especial interest. Fourcroy says ''the 

 hyacinth from Expailly was formerly placed in collections 

 of the Materia Medica to be used in some pharmaceutic 

 compositions." 



In Auvergne it is found in volcanic tufa. On Vesuvius 

 it occurs with ryacolite in white and blue octahedrons. In 

 Scotland it is found at Seal pay and in Argyleshire. In 

 Ireland with the auriferous sands. In Greenland, in New 

 Granada, and in the gold regions of Australia, it also occurs. 



Coming now to North America we have a long list of 

 localities. In Maine, at Litchfield, Paris, Mt. Mica, Green- 

 wood, Hebron. In Vermont, at Middlebury. In Connecti- 

 cut, at Norwich and Haddam. In New York, in Essex, 

 Orange, Lewis, St. Lawrence, Warren and other counties. 

 In New Jersey, at Franklin and Trenton. In Pennsylvania, 

 near Reading, in magnetic iron ore; at Easton, in talcose 

 slate. In California, in auriferous gravel in various locali- 

 ties, and in Canada, at several places. Ver}' large crystals 

 weighing as much as fifteen pounds have been found in 

 Renfrew and adjoining counties, but they are so isolated 

 that it would be impossible to obtain a large supph* there. 



