SILICA. 



265 



Fig. 163. 



FiL'. IG4. 



Lewis County. Near Natural bridge, in the town of 

 Diana, large opaque or semi-transparent crystals occur, 

 with one or both terminations perfect, in a vein in the 

 sandstone. In addition to several common forms, those 

 represented in Figs. 163 and 164 have been noticed at 

 this locality. About a mile and a half north of Natural 

 bridge, drusy quartz occurs abundantly in gcodes in 

 the sandstone. The colours are white, reddish and 

 bluish white. 



Monroe County. Small masses of hornstone, sometimes resembling calcedony, liave been 

 found in the vicinity of the city of Rochester. 



Montgomery County. At Palatine, quartz crystals occur, having one end terminated by 

 a regular hexahedral pyramid, while the other is globular and smooth as if fused. 



Near Spraker's basin, both in the towns of Root and Palatine, druses of quartz crystals of 

 considerable beauty are found, associated with calcareous spar, in the calciferous sandstone. 

 Masses of aggregated crystals are sometimes found coloured with oxide of iron, and which 

 may be called ferruginous quartz, Hornstone and coarse agate are also abundant. 



New-York County. I am not aware that crystallized quartz is met with in any quantity. 

 Inferior specimens arc occasionally found in the gneiss. Dr. Gale refers to a locality in the 

 Harlem railroad cut, about 122d-street.* Rolled masses of jasper, usually red, but some- 

 times brown, as well as the striped variety, have been found on various parts of the island 

 with hornstone. Near Kingsbridge, the quartz is sometimes fetid. 



Ontario County. According to Mr. Hall, small gcodes, lined with calcedony, occur in 

 the sandstone at Vienna, on Flint creek. t 



Orange County. The slate in this county sometimes embraces beds of quartz. Some of 

 tliem may be seen on a cross-road from Bellvale to Thomson's pond. In dip and direction, 

 they coincide with the slate in which they are embraced. Some of them are from ten to 

 twenty feet in width. The quartz of these deposits is granular, columnar and crystallized. 

 The crystals, however, are not usually perfect.f 



Four miles east of the village of Warwick, the primary form (Fig. 129) occurs in cavities 

 in jasper. The crystals are small, but very perfect. At this locality, also, are found speci- 

 mens of calcedony coating cavities in the jasper. 



At Rocky hill, in the town of Warwick, there are found crystals which vary from translu- 

 cent to opaque, of a reddish and yellowish white colour, and which resemble Hayturite. But 

 the specimens which I have seen, although unlike any of the crystalline quartz with wliicli I 

 am acquainted, are too imperfect for accurate measurement. 



Crystals similar to those represented in Figs. 130 and 131, have been found near Craig- 

 vilic ; and those similar to Fig. 132, both blue and white, occur in Warwick. 



MlN. 



* Nfw- York Geological Reports j \ 839. 



Part II. 



t Ibid. 



X Ilorton. Il)i(l. 



34 



