Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/288

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260 F³.
E. V. d’Invilliers, 1889.

It requires about 1¾ tons of raw ore to make a ton of roasted, and the latter variety is alone conveyed from the mine to the furnace.

Other indications of ore have been noticed on properties east and west of the Townsend farm; but no developments have been made as yet. There is also some little outcrop on the south side of the little synclinal valley, but the surface specimens appear to be rather siliceous.

On the south side of the main valley there is a good exposure of the Lewistown limestone in the rear of the Lewistown water-works dipping N. 20° W., 50°, and a similar one on the east side of the Kishacoquillas creek nearly opposite. Though once sparingly quarried at the point, the beds are very thin and impure, and occur near the bottom of the formation.

East of this point the Lillyville road crosses both the Lewistown and Oriskany outcrops and run through the main synclinal valley here occupied by the Marcellus and Hamilton slates. The, Oriskany sandstone, making the crest of both ridges enclosing this valley, is very fine-grained and not over 40′ thick. Its outcrop in the south ridge doubles upon itself about 2 miles east of Lewistown, with the effect of widening the valley eastward towards Maitland Station. A short distance east of doubling, a central ridge composed of Hamilton sandstone and shale rocks occupies the valley between the two Oriskany ridges and maintains that position eastward through Decatur township.

The gap in the limestone ridge north of Maitland exposes the Lewistown limestone opposite the old mill-dam, where 30′ or 40′ of good stone, associated with the middle member of the formation, dips N. 25° W., 80°. South from here a small anticlinal roll reverses the dip just at the mill, but is soon followed by a flat basin and then a 25° N. W. dip; all of which serves to broaden the outcrop of this good limestone and presents it in the gap to very favorable development.