THE MINING AND QUARRY INDUSTRY 1915 6l 



building stone just west of Saratoga Springs. On the west side of 

 the Adirondacks the Theresa limestone is described by Cushing as 

 a sandy dolomite which may in part belong to the Cambric system. 

 It is comparatively thin and has no importance for quarry purposes. 



The Beekmantown limestone, which is now taken as including 

 the middle and upper beds of that series as earlier defined, is mostly 

 restricted to the Champlain valley. It occurs on the New York 

 shore in rather small areas, usually downfaulted blocks, that are 

 the remnants of a once continuous belt. It is also doubtless repre- 

 sented in the basal portion of the limestone area that extends 

 across Washington and Warren counties. The only place where it 

 has been extensively quarried is at Port Henry where the purer 

 layers have been worked for flux. In the Lake Champlain region 

 it is a bluish or grayish magnesian limestone occurring in layers 

 from a few inches to several feet thick. 



The Chazy limestone is found in the same region as the Beek- 

 mantown in discontinuous areas along the eastern Adirondacks 

 from Saratoga county north to the Canadian boundary. It attains 

 its maximum thickness in eastern and northeastern Clinton county, 

 and has been quarried around Plattsburg, Chazy and on Valcour 

 island. The Chazy is the earliest representative of the Paleozoic 

 formations characterized by a fairly uniform high calcium content ; 

 it analyzes 95 per cent or more of calcium carbonate. It has a 

 grayish color and finely crystalline texture. The fossiliferous beds 

 afford attractive polished material which is sold as " Lepanto " 

 marble. It is used also for lime and furnace flux. There are old 

 quarries on Willsboro point, Essex county. On the west side of 

 the Adirondacks the Pamelia limestone, described in the areal 

 reports of that section, belongs to the Chazy series. It covers a 

 considerable area in Jefferson county between Leraysville and 

 Clayton, and has been rather extensively quarried for building stone 

 and lime, though of subordinate importance to the Trenton lime- 

 stones of that section. 



In the Mohawkian or Trenton group are included the Lowville 

 (Birdseye), Black River and Trenton limestones which have a wide 

 distribution and collectively rank among the very important quarry 

 materials of the State. They are represented in the Champlain 

 valley but are specially prominent on the Vermont side ; from the 

 latter area a belt extends southwest across northern Washington 

 county to Glens Falls in Warren county and is continued into 

 Saratoga county. Another belt begins in the Mohawk valley near 

 Little Falls and extends northwesterly with gradually increasing 



