gt NEW YORK STATE MUSEUM 



foreign matter to be suitable for the furnace without undergoing 

 some form of selection or concentration. In the recent operations 

 the product has been milled and separated magnetically. Peg- 

 matite and quartz are the principal foreign ingredients. Small 

 calcite veins with a deep purple fluorite also occur. In the rich 

 ore apatite is quite abundant. The results obtained by milling 

 operations show that a little less than two tons of crude ore are 

 required for one of concentrates. By the method of magnetic 

 separation some loss is entailed by the fact that the magnetise 

 has been oxidized in part to martite, which has the chemical com- 

 position of hematite and is very weakly magnetic. The analyses 

 given below communicated b}^ the Arnold Mining Co., were made 

 from samples of rich ore (i) and the admixed lean material (2). 

 Owing to the failure to determine the alkalis present, they are not 

 complete, but the discrepancy is important only in the case of the 

 lean ore which contains feldspar. The small percentages of copper 

 and nickel are, so far as known, unusual to Adirondack magne- 

 tites. These elements are probably combined with sulfur; pyrite 

 and pyrrhotite suggest themselves as the most likely combinations 



in which they may occur. 



1 2 



Fe 2 3 57-85 20.30 



FeO 27.50 10.15 



Si0 2 .: 7.62 50.82 . 



Ti0 2 39 .33 



S 038 .044 



P 2 O s 618 .43 



A1 2 3 1.68 8.32 



MnO 15 -20 



CaO 2.48 2.26 



MgO 1.26 1.53 



Cu ! 006 



Ni 072 



99.664 94-3 8 4 



Iron 61.90 23.00 



Phosphorus . 269 . 188 



Manganese .116 .155 



Titanium 24 .198 



Arnold mine. This has been the largest producer of all and for 

 many years supplied the entire output. The deepest workings 

 are about 800 feet. The loss of the main shaft by caving, 10 or 



