6 Journal of the Mitchell Society [June 



degree than in the South Mountain rocks. The depth of the 

 saprolites in the Georgia belt reaches a maximum of about 100 

 feet. 



Diabase dikes, such as are common in the Carolina belt, are 

 not found in the Georgia belt. Granitic dikes are, however, 

 not uncommon in the Nacoochee region. 



silvee 



There is very little silver alloyed with the gold that is mined 

 in the Southern States, but there are in the Carolina belt a few 

 deposits which contain a definite silver ore. This is represented 

 by what is known as the Silver Hill type of Ore Deposits, in 

 which the ores consist of a complex mixture of gadolinite, sphal- 

 erite, pyrite, chalcedony, and quartzose gangue, or as narrow 

 stringers in the schists with little or no gangue. 



Most of the silver credited to the Southern States is obtained 

 from copper ores, and therefore its production varies, as the 

 production of copper changes. It is obtained principally from 

 Tennessee with smaller amounts from jSTorth Carolina and 

 Virginia. 



GEAPHITE 



Graphite has been produced in Alabama, Georgia, and I^orth 

 Carolina ; but it is only in the former state that the production 

 has been of any very large commercial value. That produced in 

 Georgia is not used for the ordinary purposes for which graphite 

 is desired. This graphite, which only contains a comparatively 

 small per cent of carbon, is used as a filler in the manufacture 

 of fertilizer. 



In a number of the states, as in the North Carolina deposits 

 of Wake and McDoAvell counties, the graphite occurs in schistose 

 rocks, constituting from a small quantity up to 25 per cent or 

 more of the rock. The occurrence of mica and some silica in 

 these schistose rocks makes it difiicult to separate a pure graphite 

 from them. The Georgia graphite deposits, which have been 

 producing rather extensively for the last year or two, are in the 

 nature of a graphite shale or slate, containing approximately 

 13 per cent of graphite. These deposits are located near Emer- 



