new yoi:k state museum 



There are certain layers on the west side of the quarry which 



run more silicious. In structure these 

 thinner than those of the purer stone and more finely 

 ir composition was found to be as follows: 



Silica C.75 



1 1.08 



Alumina 3 . 02 



Lime 28 . 32 



17 . 94 



The best quality of stone makes a very white lump lime. 



The quarries at Tuckahoe, Westchester co., are most exten- 

 sive and are all located in the same stratum, which extends north- 

 t and southwest and has a thickness of about 40 feet. The 

 firms operating the quarries are O'Connell & Hillery, Korcross 

 Bros, and the Tuckahoe marble co., also known as J. Sinclair Co. 

 The rock in all of these quarries is a magnesian limestone of 

 granular character and moderately hard. Its character is quite 

 constant. The beds dip steeply to the west, and those forming 

 the walls of the quarry are very micaceous. 



O'Connell & Hillery 's (pi. 74) is the most southern quarry and 



is but a short distance from the Tuckahoe railroad station. The 



rock is u-ed chiefly for making lime, but in recent years the manu- 



ure of marble dust has also begun. The following analysis 



of the stone was furnished by the company. 



bonate of lime 70 . 1 



■bonate of magnesia 25.4 



jluble matter 2.4 



97.9 

 Two analyses have been priven of the stone. "No. 1 was made by 

 Prof. P. de P. RickettB, and no. 2 by W. F. Hillebrand. 



1 2 



ble 1.33 



Lime , 30.16 30 . 68 



