ADIRONDACK MAGNETIC IRON ORES 1 37 



Si0 2 67.18 



A1 2 3 17-97 



Fe 2 3 1.02 



FeO 6.13 



CaO 1.84 



MgO 1.50 



Na 2 44 



K 2 1. 12 



P 2 s 36 



MnO 30 



S 2 . 06 



99.92 



Jayville mines. Jayville is 14 miles west of Benson Mines and 

 29 miles by rail from Carthage. With the cessation of mining in 

 1888 the buildings and machinery were removed and the place has 

 since been practically abandoned, leaving only the waste heaps 

 arid pits as witness to the former activity. The mines were last 

 operated by the Magnetic Iron Ore Co., who instituted extensive 

 developments in 1886. The existence of the larger deposits at 

 Benson Mines soon led the company, however, to give up the under- 

 taking in favor of that locality. The mines are credited by Smock 

 with an output of 25,000 tons during the last period of operation. 



The ore occurrence presents a phase quite dissimilar from that 

 at Benson Mines and more like the magnetite deposits on the east 

 side of the Adirondacks. There are innumerable shoots, lenses 

 and irregular bunches in which the magnetite is found showing 

 sharp boundaries in contact with the wall rock. The latter is for 

 the most part a hornblende-biotite gneiss of sedimentary appear- 

 ance. The horizon of the ore lies close to the contact of the gneiss 

 w r ith a red pegmatitic hornblende granite. Outcrops of the granite 

 occur to the north and east within short distances where they 

 break through and cut off 'the gneiss area in such a way that their 

 intrusive character is plainly evidenced. In some of the openings 

 the granite can be seen in immediate contact with the ore. 



The openings are on the northeastern and northwestern slopes 

 of a low ridge of the gneiss that rises just west of the railroad. The 

 pits nearest the station are Hart no. 1 and no. 2, of which the first 

 is said to be 300 feet deep following a shoot 20 feet wide and 10 feet 

 thick. Hart no. 2 is much shallower. At the northeastern end 

 of the ridge where it curves to the west are the pits called New 



