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GEOGRAPHICAL AXD GEOLOGICAL DESCBIPTIOX OF GOLD BELTS. 21
Polk, McMinn, Monroe and Blount counties are probably in the same
horizon.
6. THE GEORGIA BELT.
The Georgia belt is probably of next or equal economic importance to the Carolina belt. Beginning in Rabun and Habersham counties, in the northeastern corner of the State, it extends in a southwesterly direction through the important mining town of Dahlonega, and thence to the Alabama line in the vicinity of Tallapoosa. This is in the Piedmont region of the State, lying on the southeast side of the Blue Ridge. Although the maximum width (N. \V. and S.E.) over which the mines are distributed is as great as 30 miles, the principal portion of the belt, which extends from near Canton, in Cherokee county, through Dahlonega and Xaeoocliee, to Clayton, in Rabun county, is concentrated in a width of 4 miles or less. It is to this latter portion that the following geological descriptions more especially relate.
THE COXnSTKY-BOCKS.
The rocks of this belt resemble in many respects those already described under the South mountain belt in Xorth Carolina. They are Archaean micaceous and hornblendic gneisses and schists, which probably represent sheared granitic and dioritic rocks. At the Murray mill, on Yahoola creek, near Dahlonega, a large mass of unslieared granite may be seen; and massive granite is reported to exist on Yonah Peak, near Xacoochee. These gneisses and schists are banded in narrow, lenticular-shaped layers, from 2 to 20 feet wide. A dark-colored, schistose hornblende rock, locally known as " brick-bat," is of frequent oecun'ence. Its structural relations are very difficult to determine; at times it is conformably intcrlaminated with the other schists (as at the Hedwig mine, near Auraria); again, it appears to have no regular relation in its position to the adjoining schists, which are cut off by it or very markedly disturbed in their strike, bending around the " brickbat " mass, and developing a crumpled or folded structure in the schistose laminae (as at the Singleton and Loekhart mines, near Dahlonega). It is possible that these "brick-bat" masses, which appear to be dioritic in origin, are magma tie segregations or blebs, similar to the pyroxenic and hornblendic blebs described in the South Mountain region, though, as a rule, larger. The prevailing strike of the gneisses and schists is X. 20°-30° E., and the dip 30°-60° S.E. Locally, however, in the presence of the dioritic masses, as explained above, this changes to northwest strikes with northeast dips. The rocks are often garnetiferous and contain rarer accessory minerals, such as monazite,2 though
1 See page 18, above, and Bull. 3. North Carolina Geological Survey, 1896, p. 157.
2 At the Glades Post-Office, in Hall county, 10 miles northeast of Gainesville, monazite has been found in some quantity.
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