GEOLOGICAL POSITION AND GEOGRAPHICAL DISTRIBUTION 225 



Inate over the shales. The thicker beds of sandstones are 

 generally marked by oblique lamination and cross-bedding, 

 which make it difficult and expensive to work into dimension 

 blocks. Except for flagging and stone for local use not 

 much is quarried. There are no large towns in the district, 

 and consequently the demand is light. There are however 

 some good quarries, which are worked for flagging, chiefly 

 along the N. Y., O. & W. R. R. and the u'. & D. R. R. 

 lines in Ulster and Delaware counties; and in the Catskills, 

 in Greene county there are quarries in Lexington, Jewett, 

 Windham, Hunter and Prattsville. 



Triassic Formation 



This formation, which is known as New Red Sandstone, 

 or, locally, as the red sandstone, is limited to a triangular 

 area in Rockland county, between Stony Point on the 

 Hudson and the New Jersey line ; and to a small outcrop 

 on the north shore of Staten Island. 



The sandstones are both shaly and siliceous, and the 

 varieties grade into one another. Conglomerates of varie- 

 gated shades of color also occur, interbedded with the shales 

 and sandstones. And formerly these conglomerates were 

 in favor for the construction of furnace hearths. They are 

 not now quarried. The prevailing color of the sandstone is 

 dark red to brown, whence the name " brownstone." In 

 texture there is a wide variation, from fine conglomerates, 

 in which the rounded grains are somewhat loosely aggre- 

 gated, to the fine, shaly rock and the ''liver rock" of the 

 quarrymen. Oxide of iron and some carbonate of lime are 

 the cementing materials in these sandstones. 



The well-known Massachusetts Longmeadow sandstone, 

 and the Connecticut brownstone, are obtained from quar- 

 ries in the Connecticut valley region, and of the same 

 geological horizon. The Little Falls, Belleville and Newark 

 freestones are from the same formation in its south-west 

 extension into New Jersey. 

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