weed] COPPER DEPOSITS OF THE APPALACHIAN STATES. 183 
the sandstones above the trap sheets. Reduction works have been 
erected at the Arlington property, bordering the Newark meadows, 
and at the American mine near Somerville. a 
MARYLAND. 
The Maryland properties are chiefly of historic interest, as the 
shafts and workings of most of the mines are now filled and inacces- 
sible. The Liberty mine is a noteworthy exception, and is particu- 
larly interesting because it appears to be representative of many, if 
not all, of the abandoned properties, and of many undeveloped pros- 
pects of the region. 
The deposits all occur in an open, gently rolling region underlain 
by so-called chloritic schists, whose true nature remains to be deter- 
mined. Near the copper deposits thus far examined these rocks 
appear to be altered volcanic rocks, probabty rhyolites, and resem- 
ble those of South Mountain, Pennsylvania, where copper deposits 
also occur. The Maryland ores impregnate these rocks but slightly, 
the main ore bodies occurring in what appear to be isolated blocks of 
limestone, or rather marble. The ores consist of bornite or peacock 
copper, with some chalcopyrite and associated calcite and rhodochro- 
site, and it occurs filling crevices, fracture planes, and cementing 
together the fragments of a crush-breccia of marble. 
VIRGINIA. 
Native copper occurs exposed at many localities along the Blue 
Ridge region of this State, but no workable mines have been developed 
on such properties. Copper sulphides occur, usually with large 
quantities of pj^rite, in southwestern Virginia, in Carroll and Randolph 
counties; and also in connection with pyrite and native gold in the 
old gold mines of the State. Copper ores also occur in the now vigor- 
ous^ exploited Virgilina field in Halifax Countj^ though the greater 
part of this field lies across the line in North Carolina. 
The deposits of native copper and associated oxide and carbonate 
ores of the Blue Ridge region prove to be of limited extent, and to 
have been derived from the metamorphosed and schistose basaltic 
rocks of that region. They have been designated the Catoetin type. 
The native metal often occurs in masses of several ounces or even a 
pound in weight, and is associated with epidote, quartz, and calcite, 
filling small irregular crevices along shear zones in the metamorphosed 
igneous rock. Though often traceable for miles by outcrops and 
scattered ore masses, the deposits so far explored do not go down 
more than 20 to 30 feet from the surface. 
The sulphide ores of southwestern Virginia occur beneath iron 
"Weed, W. H.. Copper deposits of New Jersey: Ann. Rept. Stale Geologist of New Jersey for 
1!M>:J, Trenton, N. J., 1903. 
