Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/304

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276 F³.
E. V. d’Invilliers, 1889.

between 3′ and 6 feet, but swelling in one place to 16′ in thickness. At the outcrop the bed dipped gently towards the south; but at 40′ beneath the surface it stood perpendicular; and at greater depth was overturned with a dip of 80° to the north. When abandoned, the bed was only about 2′ thick and the deposit is remarkable from the fact that this bed of carbonate ore had been so completely altered to brown hematite to such a great depth from the surface.

Further east in this same synclinal the Marcellus ore-bed was opened with workable size at another place, and contained a good quality of ore; but at 50′ below the outcrop the bed was unaltered and all carbonate. Here it contained 38.700 per cent. of iron; .192 per cent. of sulphur and .574 per cent, of phosphorus. with only about 6½ per cent. of insoluble matter.

The limonite ore at the surface showed 43½ per cent. of iron; .021 per cent, of sulphur and .595 per cent. of phosphorus. This opening has likewise been long abandoned,

The Minehart ore bank, 4 miles southwest of Lewistown, in the south dip of the first or Prospect Rock synclinal ridge, was opened about 25 years ago by John Minehart and was worked about 15 years ago by the Glamorgan Iron Co. This ore-bed was a little over 6′ in thickness, the ore occurring in clay derived from the decomposition of the Marcellus slate and occupying nests or pockets in the surface of the Oriskany sandstone. The general run of the ore was very siliceous, one specimen yielding, upon analysis, only 26 per cent. of iron, .046 per cent. of sulphur, .588 per cent. phosphorus, and 47.232 per cent. of insoluble residue.

Between Muthersbangh’s place on the east and Strodes Mill run on the west, the Squaw Hollow synclinal shows many abandoned ore pits, which at one time furnished more or less ore to the Lewistown furnaces and to the old Hope furnace, which stood many years ago near the forks of the stream above the entrance to Squaw Hollow on Strodes Millrun. None of this ore seems to have been of first-class quality, according to common report; but the openings in it are almost numberless, and being mainly worked to