THE ADIRONDACK MOUNTAINS 79 



Other iron mines. Aside from the locality just described, there 

 are many places where magnetic iron ores have been more or less 

 mined during the last one hundred years, but only the more import- 

 ant ones are considered. 



The greatest iron mines in New York State are in the vicinity of 

 Port Henry, Essex county. Of these the oldest is what is now 

 called the Cheever mine (north of Port Henry) which was first 

 worked late in the eighteenth century. But still greater ore deposits, 

 known as early as 1835-40, are at Mineville, 6 miles northwest of 

 Port Henry, where two companies own property. All the mines 

 mentioned are now in operation, their total production to date being 

 no less than 25,000,000 tons. The ores are crushed and then con- 

 centrated by a magnetic separation process. They are very pure and 

 of high grade. Approximately 1,000,000 tons a year are now taken 

 out. 



In the vicinity of Hammondville, Essex county, are other con- 

 siderable iron ore mines, the first of which was worked in 1824. 

 These mines were most active from 1873 to 1890, ceasing to operate 

 in 1893. xA.bout 2,000,000 tons of ore have been taken out. 



In southern Clinton county (near Ausable Forks) there are several 

 magnetic iron ore deposits, especially the Arnold Hill and Palmer 

 Hill mines, the former having been intermittently worked from 1806 

 to 1906, and the latter between 1825 and 1890. Altogether about 

 2,000,000 tons of ore have been removed. 



The Lyon Mountain magnetic iron ore mines are situated near 

 Dannemora in Clinton county. Mining began there in 1871, and 

 still continues very actively. The ores are extensive and of high 

 grade. Approximately 4,000,000 tons of ore have been mined. 



Though early known, systematic operations did not begin at the 

 Benson Mines in southern St Lawrence county till 1889. Work has 

 been rather intermittent since then. Several hundred thousand tons 

 of ore have been removed. 



Graphite mines. As already stated, flakes of graphite (so-called 

 " black lead ") are of common occurence in certain strata of Gren- 

 ville age. At several localities much graphite has been mined. 



By far the most important mine is that owned and now operated 

 by the Joseph Dixon Crucible Company at the village of Graphite 

 in Warren county. A hard quartzite rock, distinctly stratified in 

 relatively thin layers, contains the graphite. This rock is mined by 

 underground methods, crushed, and the flakes of graphite separated 

 bv mechanical means. This is one of the most important graphite 



