QUARRY MATERIALS OF NEW YORK 197 



north and south on the New York-Connecticut boundary. The sur- 

 face is flat or slightly hilly in contrast with the rugged outcrop of 

 the gneiss. The limestone maintains a nearly uniform course 

 slightly east of north and shows usually an easterly inclination, but 

 for short distances the dip may change to the west. Along with 

 the limestone appears a white quartzite that may be seen a little to 

 the west of the quarry openings. 



The product of the quarries is a uniform white marble suited for 

 building and interior work. The grain is fine ; the particles 

 average from .75 to 1 mm diameter and are prismatic or subrounded 

 in form. In the exposed beds the marble appears very compact and, 

 except for the upper few feet just below the soil, is neither stained 

 nor weathered. Its appearance in thin section is shown in figure 17. 

 Physical tests indicate a specific gravity of 2.86, ratio of absorp- 

 tion .144 per cent, and pore space .51 per cent. The weight is 

 178.5 pounds to the cubic foot. Strength tests made by Prof. Ira H. 

 Woolson in the laboratories of the School of Mines, Columbia 

 University, gave ultimate resistances to compression of 17,401 

 pounds to the square inch on one sample, 18,836 on another and 

 20,882 on a third, tested on the bed. 1 An analysis supplied by the 

 company indicates that the lime and magnesia occur in the propor- 

 tions of a true dolomite. 



Si0 2 .70 



AI2O3 .37 



Fe 2 3 .25 



MgO 20.25 



CaO : 30.63 



Na 2 .12 



K 2 .46 



Loss and undet .56 



C0 2 46.66 



100.00 



The company has two quarries, the one being on the east slope of 

 a low ridge facing the gneiss ridge and the second a little farther 

 up the slope and northwest of the first. The lower quarry has an 

 extreme length of 250 feet, a width of 150 feet as a maximum and 

 a depth of 135 feet. There are three derricks in place. The other 

 opening is 150 feet long, 75 feet wide and about 60 feet deep. It 

 has two derricks and an overhead cableway, the latter for carrying 



1 U. S. Geol. Surv. 20th Ann. Rep't, pt 3, p. 422. 



