THE MINING AND QUARRY INDUSTRY I906 37 



Alumina (AI0O3) tr 



Manganous oxid (MnO) .63 



Lime (CaO) 5.51 



Magnesia (MgO) i . 19 



Carbon dioxid (CO^,) i .05 



Water (H.O) 20 



99-44 



The company owns a furnace at Secaucus, N. J., to which the 

 ore is shipped. In order to reach the Hudson river, a tramroad 

 4 miles long has been built. At the terminal of the road the ore 

 is loaded into the buckets of an aerial rope conveyor, 6300 feet 

 long, which carries it to the dock at Fort Montgomery where there 

 is a 1 000- ton storage bin. The power for driving the air compressor 

 and pump at the mine is taken from the adjacent Popolopen creek. 



Caledonia mine. This mine situated in the hematite district 

 of St Lawrence and Jefferson counties has been operated in recent 

 years by the Rossie Iron Ore Co. It has furnished altogether prob- 

 ably 500,000 tons of ore. The record for the past year has been a 

 very creditable one, the output having been more than double that 

 for 1905, while large resources have been opened for future exploita- 

 tion. The company has recently enlarged and improved its surface 

 plant which will enable it to increase the production still further. 



The ore is a fairly rich soft hematite, running from 50 to over 60 

 per cent in iron. Its quality seems to improve somewhat with the 

 progress of mining in depth. 



It carries a relatively high proportion of lime which with its ex- 

 cellent physical character makes it very adaptable to furnace treat- 

 ment. A rough sorting is required to remove admixed rock, and 

 about one fourth of the material hoisted is thus rejected at tlie sur- 

 face. An analysis^ of shipping ore shows the following chemical 

 constituents : 



Iron ( Fe) 52 . 71 



Silica (SiOs) 10.12 



Alumina (AI2O3) 7.04 



Manganous oxid (MnO) i .69 



Lime (CaO) 7.04 



Magnesia (MgO) 0.38 



Carbon dioxid (CO2) 5.41 



Sulfur (S) .03 



I See article by Robert B. Brinsmade, Eng. & Min. Jour. Sept. is, 1906. 



