MURPHREE'S VALLEY ;, ECONOMIC GEOLOGY. 101 



impurities, than is usual with limonite, and is therefore a 

 very promising ore for the manufacture of steel. 



Near this deposit on the S. E. side, is another deposit of 

 limonite, which though locally adjacent to the Lower Limo- 

 nite, is widely separated in geological position and time. 

 It is the 5th deposit in the scale. It belongs to the Sub- 

 Carboniferous horizon, just beneath the LaGrange sandstone. 

 Its presence here adds much to the importance of this 

 locality. And for the sake of greater compactness of de- 

 scription, will be presented here, out of its order, but in its 

 association. 



Immediately on the S. E. side of the great fault, in the S. 

 W. i of S. 5, T. 13, R. 2 E., is the exposed edge of a great 

 deposit of limonite ore. On the N. W. side ot it is a slice of 

 Lower Siliceous strata, crumbled and comminuted, yet 

 clearly showing the structure, and fossils of that period. A 

 little farther to the S. W. the unmistakable Black Shale 

 makes its appearance. On the South and Southeast of the 

 ore, the LaGrange sandstone is plainly seen. The dip of 

 all, as usual, is to the N. W. The geological position of this 

 ore deposit is therefore demonstrated. The deposit appears 

 to be about 50 feet thick. Though from evident slides on 

 the S. E. side, its base could only be approximated. The 

 upper portion of this deposit is generally too sandy. The 

 larger portion of the ore is of that character for the upper 

 eight or ten feet. Then a fair to good class of ore is carried, 

 generally, in the remainder. The ore is not as uniformly 

 good as in the Lower Limonite deposit, yet it has some ore 

 equal to the best of that. Much of this ore is in large blocks 

 and bowlders, and it is evidently more closely compacted, 

 with less irony clay associated with it, than the other de- 

 posit. The larger blocks are generally near the upper part 

 of the deposit, while near the base, it is in smaller pieces. 



Southwest from this point it soon disappears beneath the 

 surface, and but little of it is seen farther down. It prob- 

 ably diminishes in volume very rapidly in that direction. 

 In the S. E. i of Sect. 5 most of the deposit has been swept 

 away, on^v a thin stratum of its base is occasionally seen. 



