104 



NEW YORK STATE MUSEUM 



It is expected to increase the production very largely during the 

 present year. A new 20 drill air compressor and other additions 

 to the mining plant are being installed which will facilitate operations. 



Old Sterling mine. Work at this mine in the town of Antwerp, 

 Jefferson co., was resumed during the past year by the Old Sterling 

 Iron Co. The mine has been operated since 1836, with occasional 

 interruptions and has yielded a large output. It was last closed 

 down in 1902. 



The deposit lies on the contact between Potsdam sandstone which 

 forms the capping and Precambric crystalline rocks. The walls 

 consisting of so called serpentine are irregular and send out off- 

 shoots into the ore. The serpentine is considered to be an altered 

 form of granite and gneiss which are exposed in the immediate 

 vicinity of the deposit. Its chemical composition differs materially 

 from that of true serpentine, analysis showing only small amounts 

 of magnesia and much alumina. 



The workings include a large open pit at the north, now aban- 

 doned, and an extensive system of drifts and chambers from which 

 the output has been obtained in recent years. The ore varies 

 from specular to earthy red hematite. The following analysis has 

 been taken from the report by Smock. 



Ferric oxid (Fe,0 3 ) 79 .52 



Silica (Si0 2 ) 9.80 



Sulfur (S) 08 



Phosphoric acid ( P 2 O ) . 263 



Alumina (Al 2 O s ) 1. 12 



Lime (CaO) 2.49 



Magnesia (MgO) 1 .07 



Water (H 2 0) 68 



95-023 



Total iron 55-66 



Phosphorus .115 



An analysis of a large shipment from the mine, quoted by Putnam, 

 gave: iron 41.92 per cent; phosphorus .130 per cent. 



Clinton mines. The hematite mines at Clinton continue to fur- 

 nish some ore, .though the output for the past year or two has been 

 small, due to the closing down of the blast furnace at Franklin 

 Springs. At present mining is limited to the property of C. A. 

 Borst who supplies ore for paint manufacture, principally to the 

 Clinton Metallic Paint Co. 



