298 NEW YORK STATE MUSEUM " 



waters. There are quarries in the Chazy, Trenton and Becraft 

 Hmestones that have produced stone for decorative purposes. 



The marble quarries reported a more active business last year 

 than in 191 5, which was an exceptionally dull season. The value 

 of the output reached $268,391, of which about 50 per cent repre- 

 sented building marble, or in exact figures $133,238. Monumental 

 stone accounted for $75,587 and other kinds for $59,566. There 

 were 8 quarries altogether in operation distributed among Clinton, 

 Warren, St Lawrence, Dutchess and Westchester counties. 



SANDSTONE 



Among the sedimentary formations which occur in the State,' 

 sandstone probably has the largest areal distribution, while in 

 economic importance it has normally ranked second to limestone. 

 Nearly all the recognized stratigraphic divisions above the Archean 

 contain sandstone in one or more horizons. The kinds chiefly 

 quarried are the Potsdam, Hudson River, Medina, Hamilton, 

 Chemung and Portage sandstones. A few quarries have been 

 opened also in the Shawangunk grit, the Rensselaer grit and the 

 Clinton and Triassic sandstones. 



Of the Potsdam sandstone, which represents the Upper Cambrian 

 in New York State, the most extensive outcrops occur along the 

 northern and northwestern borders of the Adirondacks, in Clinton, 

 Franklin", St Lawrence and Jefferson counties. Other exposures 

 are found in the Lake Champlain valley and a few uneroded rem- 

 nants occur in the Mohawk valley. The sandstone in many places 

 has the character of quartzite, consisting of quartz grains cemented 

 by a secondary deposition of quartz, and is an exceedingly hard 

 and durable material. It is the purest of the sandstones and in 

 certain exposures carries over 95 per cent silica. There are some 

 beds which are adapted for glass-making or for the manufacture of 

 metallic silicon and ferrosilicon, and in fact the latter products are 

 now being made from this material. The principal quarries of 

 building stone are situated near Potsdam, St Lawrence county. 

 Redwood, Jefferson county, and Malone and Burke, Franklin 

 county. 



The Medina sandstone has been quarried extensively for build- 

 ing stone, paving blocks and curbstone, and there is still an 

 important industry based on the production of those materials in 

 Orleans and Niagara counties. It is a fine-grained sandstone of 

 pink, white and variegated color. The pink is an excellent free- 

 stone that has been employed in many of our cities for large 

 structures. 



