SMITH COUNTY. 211 



thickness. It is flat on top, but is bulging and mammillary below, and lies 

 at or near the summits of the highest hills in the region. In fact, it is to, 

 this protecting cap of hard material that the hills owe their existence, as it 

 has saved the underlying strata from the effects of erosion, which otherwise 

 would quickly have lowered them to the level of the surrounding rolling 

 country. The iron ore bed is directly underlaid by a deposit of a soft yellow 

 indurated glauconite (greensand) varying from thirty to forty feet thick. 

 This bed is sometimes hardened into a soft rock, easily cut with a saw or an 

 axe, and locally used as a building stone The interior of the bed, however, 

 where it has not been exposed to the atmosphere, retains the dark green 

 color of the unaltered greensand. It contains considerable iron pyrites and 

 numerous casts of fossils of the Claiborne Epoch, and represents the entire 

 north extension of the Smithville beds of the Colorado River. This in turn 

 is underlaid by a great series of sands and clays, for a description of which 

 see the Timber Belt beds." 



This description, which was intended for the whole area of Eastern Texas, 

 fits admirably the ores of Smith County, hence I have given it in full. 



Localities. — The first locality at which I examined the laminated ore was 

 on the J. B. Chancellor headright, eight miles southeast of Tyler. Here the 

 ore was seen in large quantities, covering an area of about four square miles. 

 It is of the black and brown laminated variety, the laminae on the surface 

 preserving a resinous lustre, showing iridescent colors, but on breaking open 

 a piece of the ore the rich characteristic chestnut brown color is seen. The 

 ore crops out on the brink of the ridge, and is from six to ten inches in 

 thickness. 



The ridge itself is covered by a dense growth of blackjack oaks, hickory, 

 etc., and is cut by numerous deep ravines and hollows. At this locality may 

 be seen also the typical bench structure of the iron ore regions, which here 

 are two in number. The ore is overlaid by from one to twenty feet of soil 

 and sand, and has a thin veneering of sandstone from one-half to two inches 

 in thickness on it. It is underlaid by from ten to twenty feet of soft indu- 

 rated greensand, in which a few casts of fossils and calcareous concretions 

 were occasionally seen. The greensand is in turn underlaid by a series of 

 red sandy clays containing thin seams of iron ore and ferruginous pebbles. 

 A section of the various strata gives: 



1. Sand and soil 1 to 20 feet. 



2. Siliceous sandstone. ... ' . i to 2 inches. 



3. Laminated iron ore 6 to 10 inches. 



4. Altered greensand 10 to 20 feet. 



5. Red sandy clays, at base exposed to view. 60 feet. 



About five miles southwest of this point, and seven miles west of Troupe, 

 21— geol. 



