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NEW YORK STATE MUSEUM 



way in which the f c serpentine " rock is mixed with the hematite, 

 but their general structure is- that of stratified bodies. The cap 

 rock is a sandstone ; the bottom rock, slaty beds, underlain by a 

 white, graphitic, cryst dime limestone. From the variations in 

 the ore, as tested by borings with the diamond drill at the 

 Caledonia mines, it seems reasonable to assume the existence of 

 two classes of deposits — one, the originally stratified sheets, and 

 the other, secondary deposits in smaller and irregular shaped 

 pockets. 



The hematite of these mines is generally firm and massive, of a 

 deep red color, soiling whatever it touches. In some of the mines 

 there is a specular ore, which has a crystalline structure, metallic 

 lustre and is of a steel-gray to black color. Calcite, carbonate of 

 iron, ferruginous quartz, pyrite and millerite occur in the ore. 

 These ores average from 48 to 53 per cent, of metallic iron. They 

 contain an excess of phosphorus above the limit demanded by 

 furnace managers for makiag Bessemer iron. For mixing with 

 more refractory ores they are sought after, being almost self-flux- 

 ing. In the market they are often known as " Antwerp red 

 hematites " and " Rossie hematites." 



Charcoal furnaces were built early in this century at Rossie, 

 St. Lawrence county, and at Sterlingville and Antwerp, in Jeffer- 

 son county, for smelting these ores. Of the older mines the 

 Shirtliff and Tate and Polly have been abandoned. Two new 

 mines have become producers, the Clark and Pike. The total 

 production of the district was 110,000 gross tons in 1888. 



IV. The Clinton or Fossil Ores. 



The red hematite of the Clinton group bears several names ; 

 thus : From its aggregated grains it is termed " oolitic ore " or 

 "lenticular iron ore;" from its fossiliferous character, it is 

 widely known as "fossil ore," and from its place in the 

 geological series, it is often called " Clinton ore." It is remarkable 

 for the thin, yet persistent beds over wide areas, which lie 

 between green shales and calcareous strata. Following the out- 

 crop of the Clinton group, the ore has been found in Herkimer, 

 Oneida, Madison, Cayuga, Wayne, and Monroe counties. West 



