Art. IX.] Watson, Manganese Ore- Deposits of Georgia. ijj 



is a long, narrow strip or belt of shale which marks the position 

 of a valley for several miles in a north-south direction. The 

 western margin of the valley marks the position of a minor- 

 thrust fault, and to the eastward across the valley, about ^ of 

 a mile, the shales are overlain by the heavy beds of cherty 

 limestone. The ridge is a low one, averaging more than lOO 

 ft. in elevation along its highest portions, and its surface is ir- 

 regular and broken by erosion. In places, it is covered with 

 chert-fragments of all sizes in various stages of decay. (See 

 Figs. 13 and 14.) 



About ^ of a mile south of Lindale, on the west slope of 

 the valley and about 40 ft. above the valley-bottom, a number 

 of openings were made in the residual cherty clay, derived from 

 the decay of the Knox dolomite, for manganese. Red, yellow, 

 white, buff and purple-colored clays make up the residual cov- 

 ering in which the manganese openings were dug. Red clay 

 is the surface covering, and will average less than 5 ft. in thick- 

 ness. The underlying yellow clay which predominates is 



Fig. it, 



Cross-Section of Valley, ^ mile South of Lindale, Floyd Co., Georgia, 

 Showing the Position of the Manganese-Deposit and the Relations of the Un- 

 derlying Rocks. 



A, residual clay, containing admixed chert and partially decayed rock-frag- 

 ments ; B, Knox dolomite; C, Conasauga shale. The black area is manganese. 



highly siliceous and freely mixed with large and small chert- 

 fragments, usually in an advanced stage of decay. The clays 

 usually show partial stratification, the bedding planes conform- 

 ing in a general way with the ridge-slope. They thin toward 

 the top of the ridge and are the thickest in the valley. 



The ore is distributed through the clay in the form of 



