44 GEOLOGICAL RECONNOISSANCE 



White river, unless it be in small quantities, associated with the lead and 

 zinc ores of this country. 



The grey and red varigated limestones, which will be hereafter spoken 

 of, under the head of Marion county, occur in the bluffs of White river, 5 

 or 6 miles above the mouth of the North Fork, and a mile above Big creek; 

 but they lie under a heavy mass of superincumbent rock, which makes 

 them difficult of access. 



The cherty magnesian, and other varieties of limestones, of which the 

 base of the hills is composed, and which form bold cliffs on the North Fork, 

 and at Ware's mill, appear to be of silurian date, but the sandstone chert 

 and limestones towards the tops of the ridges, must belong to the subcar- 

 boniferous group, judging from the few imperfect fossils found. 



J. E. Ware showed me some ores of manganese, which he says came 

 from the bluffs of White river, below the mouth of Big creek. 



On the south side of the North Fork, the chert frequently assumes the 

 character of hornstone and agate. 



There are very fine buhr millstone rocks in the ridges of the North Fork, 

 not far from Ware's mill, but on the opposite side of the river, according 

 to J. E. Ware; he also found small particles of copper ore and some Terra 

 Sienna on a prong of Morton creek, on section 17, township 18 north, range 

 12 west; but though he has searched a great deal for ores, adjacent to the 

 surrounding country in Izard, he never discovered any deposit or vein of 

 copper worth following by drifts or adit levels. 



Near the line between Izard and Marion counties, at Camp spring, there 

 is a bed of brown ochreous clay, which produces a color similar to Terra 

 Sienna. The bed is in a ravine, about 6 or 8 feet under the spring. It is 

 of various shades at the outcrop, mostly on account of admixtures of 

 earths washed over it. Farther in the bank it could, probably, be obtained 

 in greater purity, and of deeper and more uniform tints. 



Lower down, on the same branch, are extensive beds of buhr millstone 

 in " Camp creek hollow." some of which are of excellent texture and 

 hardness for grinding corn, while other varieties are equally good for 

 wheat. This buhrstone lies some 200 feet below the level of the ridge 

 over which the Yellville road runs, above the Camp spring. 



In consequence of the vegetation and debris of rock concealing the 

 strata, no very satisfactory section could be obtained of the whole of the 

 members composing the hills forming the Camp creek hollow; but the 

 following is the succession from above, downwards, of those which can 

 be seen: 



1. Carboniferous limestone and chert. 



2. Sandstone. 



