LIME AND CEMENT INDUSTRIES 791 



Silica 6.5 



Alumina 1.67 



Ferric oxid 76 



lime carbonate 88 . 44 



Magnesium carbonate . . 2 . 68 



100.05 



This same stone outcrops for some distance along the railroad 

 track south of this point. 



South of Leyden and below the railroad level is a large quarry 

 of black, finely crystalline limestone on the land of Mrs Christy. 

 The stone has thus far been used for building purposes only. It 

 probably represents the Trenton proper. It is of greater purity, 

 however, as shown by the following analysis. 



Silica 1.44 



Alumina ) 8 « 



Ferric oxid ) 



Lime carbonate 97 . 36 



Magnesium carbonate 1 . 04 



100.67 



The Trenton limestone has been quarried for lime burning at 

 Collinsville 3 miles north of Port Leyden. The rock here as 

 exposed in Roberts's lime quarry is a coarse grained, gray stone, 

 in thin layers 2 to 8 inches thick and often containing irregular 

 partings of bituminous shale. They so predominate at times as 

 to give the rock a shaly character, and such portions are discarded. 

 The stone makes a white lime, as might be expected from its low 

 silica and iron percentage. The composition of the stone as an- 

 alyzed by Mr Newland is as follows: 



Silica ' 3.09 



Alumina 1.15 



Ferric, oxid • • »49 



