QUARRY MATERIALS OF NEW YORK 87 



Sulphur was tested for, but not found. Analysis i represents 

 the coarse massive granite from milestone 59. Analysis 2 is based 

 on the finer grained massive rock from milestone 62. No. 3 relates 

 to a sample taken from near the eastern edge of the area at mile- 

 stone 64, which shows a strong cataclastic texture. 



Physical tests. The following tests of the coarse and fine sorts 

 of the granite from Jayville were made in the laboratories of the 

 State Museum. The samples were taken from the natural outcrop. 



Specific gravity 2 . 70 2 . 63 



Weight, pounds a cubic foot 168.5 164. 1 



Ratio of absorption, per cent .31 .264 



Pore space .99 .69 



THE DIANA-PITCAIRN SYENITE 



The syenite intrusion, previously mentioned as forming the west- 

 ern boundary of the red granite in southern St Lawrence county, 

 needs only brief description in this place. It can not be considered 

 to offer opportunity for the extraction of building materials on a 

 large scale, though the massive phases of the rock are well adapted 

 for highway and concrete material. The somber color which is 

 generally characteristic of this rock in the Adirondack exposures 

 is unsuited to most architectural purposes. 



The syenite area is well shown on the large geological map of 

 the State. Its boundaries were traced by C. H. Smyth, jr, who 

 has also given a detailed account of its geological and petrographical 

 features in his paper on " Crystalline Rocks of the Western Adiron- 

 dack Region." 1 The intrusion extends in a northeast, southwest 

 direction across the townships of Diana, Lewis county, and Pitcairn, 

 St Lawrence county, for a distance in all of 20 miles. Its width is 

 usually less than 5 miles and its area may be estimated at not less 

 than 75 square miles. The Carthage & Adirondack Railroad, after 

 passing out of the red granite near milestone 56, crosses the north- 

 ern part of the syenite intrusion and enters the limestone belt on 

 the west just beyond Harrisville. The railroad again follows the 

 syenite for some distance in the stretch from Bonaparte lake to 

 Natural Bridge, near the southern end of the intrusion. 



The syenite is grayish green to dark green, heavy and very tough 

 rock composed largely of feldspar but containing considerable 



1 N. Y. State Museum Report 51, v. 2, 1899. 



