THE MINING AND QUARRY INDUSTRY I912 71 



doubtless 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 Beekman- 

 town 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 re- 

 ports of that section, belong 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 

 width across Oneida, Lewis and Jefferson counties to the St Law- 

 rence river. There are isolated areas of Trenton limestones in the 

 Hudson valley south of Albany. The limestones vary in composi- 

 tion and physical character according to locality and geologic posi- 

 tion. They are often highly fossiliferous. In the northern section 

 they are mostly gray to nearly black in color, contain little mag- 

 nesia and run as high as 97 or 98 per cent calcium carbonate. The 

 lower part of the group is heavy bedded and well adapted for build- 



