242 ECONOMIC GEOLOGY 



treads of a stairway. The ores are blended to a shipping grade, 

 and sent to the lowlands on aerial rope ways, conveyed to the 

 coast by ground trams, transferred to lighters, and then con- 

 veyed to ships. The quantity of ore seems to be inexhaustible. 

 The ores are shipped to England, France, Holland, Germany 

 and Australia. 



Geographical Distribution of Nickel. There are three distinct 

 belts of nickel-bearing ores in the United States: (1) The Ap- 

 palachian district; (2) the Central district; and (3) The Cordil- 

 leran section. 



(1) Appalachian belt: But little nickel has ever been produced 

 in this section. The largest deposit is in Lancaster County, 

 Pennsylvania, where the nickeliferous pyrrhotite is associated 

 with the altered intrusive, amphibolite, encased in mica schist. 

 J. F. Kemp regards the amphibolite as an altered gabbro or 

 norite, and the deposit as originally magmatic. 



In the southern Appalachian belt in Webster County, North 

 Carolina, the hydrous silicates of nickel appear in connection 

 with the transition of a peridotite magma (dunite) to serpentine. 

 The olivine of the original peridotite bears nickel. The nickel 

 ore occurs in small fissures with talc and gymnite. 



(2) Central district (Mo.) comprises the Mine La Motte, 

 Fredericktown district, which furnishes annually a small amount 

 of nickel as a by-product from the lead industry. Nickel was 

 mined and smelted to a small extent by the North American 

 Lead Company. 



(3) Cordilleran section: This section embraces Arizona, Idaho, 

 Oregon, Washington, and Wyoming, each of which have from 

 time to time reported the existence of nickel-bearing minerals, 

 but none have ore bodies that have yet assumed the dimensions 

 of commercial importance. The most noted of these occurrences 

 are those of Nickel Mountain, Oregon. According to H. Ries 

 the ore is genthite associated with a quartz gangue. It occurs as 

 a flat-lying deposit on the surface of a post-Cretaceous, pre- 



" Eocene peridotite, or as veinlets in the peridotite and resulting 

 serpentine. It is thought that the genthite represents an 

 alteration product of the peridotite, for nickel has been found 

 in the fresh peridotite. 



Other Districts. At Sudbury, Ontario, is by far the largest, the 

 best known and the most important nickel-bearing ore body in 

 America. From this nickeliferous pyrrhotite comes nearly all 



