COPPER DEPOSITS OF THE APPALACHIAN STATES. 
By Walter Harvey Weed. 
INTRODUCTION. 
Copper deposits occur at intervals along the Appalachian Mountains 
and the Piedmont Plateau to the east, extending from Canada to 
Alabama. The earliest known copper mines of the continent are 
included in this region, and many interesting historical facts are 
associated with them. The geology of so extensive a region is neces- 
sarily varied. The rocks are in most cases metamorphosed and of 
the types known as chloritic schists and hornblende-schists ; but their 
true nature is disclosed when the methods of modern petrographic 
research are applied to them, and in most cases the original nature 
and origin of the rock can be made out. It would be surprising that 
these deposits have not been studied in the light of our newer knowl- 
edge, both of petrology and of ore deposits, were it not for the fact 
that for many years past they have been of but little or no economic 
importance, and their workings have been filled by water and inac- 
cessible. 
While engaged in the collection of data to support or disprove the 
theory of secondary deposition and enrichment, a number of these 
old and formerly well-known mines were examined, as well as several 
newer properties whose development was inspired by the remarkably 
high price of copper in 1900-1901. The result of these examinations, 
necessarily brief and made primarily for the object stated, has been 
in part already published, but, the subject appearing attractive and 
the investigation timely, it was decided to extend the work and, from 
time to time, as opportunity offers, to examine and study all the 
known copper deposits of the Eastern, Middle, and Southern States. 
Early in this work it was recognized that, while many deposits arc 
of similar character, others present marked differences in mineral 
contents, structural character, and association. This led to an attempt 
to group deposits of similar nature, so that a description of a type 
would answer for many. This was done in a paper entitled "Type 
Copper Deposits of the South. " a Since then several copper properties 
in Maryland and New Jersey have been examined and found to be 
still different in character from those described. 
-(Trans. Am. Tnst. Min. Eng., 1899. 
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