rQRE state MUSEUM 



of the c unity are B continuation of the Orange 

 Silurian Limestone belts. The former are meta- 

 ii. 1 partake of the nature of marble, being 

 \\ bile the latter are not. 



While there arc outcrops of the limestone 

 i mini: in the valley followed by the Harlem rail- 



d, only two larg aings have been made. These are at 



Plains and South Dover. 



A- Dover Plains, <•. A J. EL rletcham have operated a quarry 



aloi highroad one half mile southeast of the town. The 



. is a soft, fine grained dolomite of gray or white color. The 



is about 200 feet Long, 20 to 30 feet wide and 10 feet 



p. No analysis was made of the stone but several samples 



were examined to determine their insoluble matter, which ran 



m 2 to • 



South Dover marble co. has a large quarry (pi. 34) on the 

 hill 2{ miles northeast of the station. The rock is a fine grained, 

 white dolomite and has hitherto been used only for structural 

 purposes. It lias to be hauled to the railway. In appearance it 

 is very free from impurities. The following analysis of the rock 

 furnished by the superintendent of the company. 



Si ica 7 



Ferric oxid 25 



Alumina 37 



Lime 30. G3 



gnesia 20.25 



8 i 12 



1 '• tash 4(j 



The atone i- broughl down to the railroad over a private trolley 



Limestones in the western part of tlie county are usually a 



ained bluish -ray rock, containing le^s magnesia than 



biter phases to the southeast and east. It has been used 



on the whoL silicious that the resulting Lime 



n. 



