410 GEOLOGY OF OHIO. 
of the Upper Freeport clay, underlying the coal of the seam, and, con- 
sequently, the blackband by 5 to 15 feet. The Straitsville ore is borne 
by or replaces the Upper Freeport limestone, which is here separated 
from the coal by an interval of 20 to 30 feet. The Straitsville ore is 
thus 60 to 70 feet above the main coal (No. 6), and the Buchtel ore, 
80 to 90 feet above the same base. ‘The usual interval between the two 
ore horizons is 15 feet. 
Both of these ores are local in their occurrence, and they are not 
by any means persistent beds. The Buchtel ore has by far its best 
development in the vicinity of Buchtel Furnace, where also it has been 
largely worked, and the location of which was fixed in part by the 
presence of these deposits; the Straitsville ore has been mined in the 
large way at but a few points, viz., in the hills adjacent to New Straits- 
ville, from which several thousand tons were taken out a few years 
since, and from the vicinity of Moxahala, where many unsuccessful 
efforts have been made to find in it a safe basis for iron manufacture. 
It is known here as the Sour apple ore, or as nodular ore. 
The Buchtel ore is a lean carbonate of iron, always calcareous, and 
often passing by easy gradations into an impure limestone. The nodules 
or bowlders that compose it are of large size, and are very hard and 
heavy. They are imbedded in clay, and are light gray in color, some- 
times inclining to blue. The thickness of the seam at its best is between 
5 and 6 feet, and there are considerable areas where it exceeds two feet 
in thickness. The upper portion, where the seam is thickest, generally 
consists of a separate layer of nodules, more calcareous than the main 
seam, and called, distinctively, bowlder ore. ‘The outcrop ore is rough 
and unpromising for the most part, though an occasional mass of fair 
quality is found. Analysis of seven samples, selected from the stock 
pile of calcined ore at Akron Furnace, when the seam was first worked, 
showed an average of a little less than 21 per cent. of metallic iron 
(Howard). The bowlder ore was mined with the rest of the seam at 
this time. When this is left out, the percentage runs higher. The 
best of the calcined ore is said to yield 33 per cent. in the furnace. 
There is a considerable amount of lime in it, but the proportions are 
entirely uncertain, and it can never be safely used for flux. There is 
no way of knowing what proportions of iron and lime go into the fur- 
nace top where the products of this seam are used. 
The same seam has been mined on a large scale at the new furnaces 
g 
