MINERAL RESOURCES OF THE STATE OF NEW YORK 1 25 



that the product was suitable for Bessemer iron, in which case the 

 ore was probably roasted. The mine was last worked in 1881 by 

 W. H. Campbell. A tramway was used for carrying the ore to 

 the Hudson river at Peekskill. 



The Todd is on the same side of the valley 3 miles from the Croft 

 and the same distance from Peekskill. It is near the contact of the 

 crystalline limestone and the gneiss which forms the ridge directly 

 west, and is based on small ore shoots that have been explored in 

 three pits. The eastern wall is limestone while on the west side 

 the ore is bordered in part by fibrous amphibolite schist. The 

 strike of the shoots is northeast and their dip vertical. The ore 

 carries around 45 per cent iron and contains hornblende, epidote 

 and chlorite, showing secondary alteration. The property during 

 the last period of operations (1880) belonged to the Fallkill Iron Co. 

 who operated furnaces at Poughkeepsie. It is novi^ included in the 

 estate of Stuyvesant Fish. 



Croton mine. This is a large low-grade property, on an ore zone 

 that extends some 5 miles in a southwest direction from Brewster. 

 The mine is about in the middle of the zone, while the Brewster 

 mine is at the north end and a third working lies near the south 

 end, one-half of a mile west of Croton Falls. Work has been carried 

 on at different times, the last period of active mining began in 1899 

 and lasted for a few years. Magnetic concentration was employed, 

 but at that time the process was not well developed and difficulties 

 were encountered with the pyrrhotite which accompanies the magne- 

 tite. The deposit has been explored for a distance of 2500 feet on 

 the strike and is opened by a tunnel 1400 feet at an average depth 

 of 135 feet from the outcrop. The width of the stopes ranges from 

 50 or 60 feet to 100 feet or a little more. The ore is not sharply 

 defined along the walls in most places, but shades off into the country 

 through a gradual decrease in magnetite, the gangue being of the 

 same mineral nature as the inclosing rock. The latter has the 

 composition of augite syenite and closely resembles the ore bearing 

 syenite gneisses of the Adirondacks. In 19 12 plans were under 

 consideration for reopening the mine; it was proposed to erect a 

 mill of 1500 tons daily capacity, using the wet magnetic method 

 of concentration and roasting the concentrates to free them of sulphur. 

 Experimental tests with the process indicated a product coiild be 

 made with an average of 64 per cent iron, after crushing through 

 20 mesh screens, with a phosphorus content of .03 per cent arid 

 sulphur . 3 . Foundations were laid for the mill, but the plant was 

 not completed. 



