Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/312

284 F³. “Jack,” the upper one furnishing most of the commercial ore. The bed has a yellow slate roof and a sandstone foot wall, and has been developed for about 50 yards east and west of the shaft. Preparations were being made for reaching this bed at a low level by means of a tunnel of considerable length driven across the measures, and thus provide for natural drainage and a more economical method of mining. It is claimed that this ore is one of the Danville beds, beneath the Ore sandstone, and that it is the same as developed at McGill’s and Kinsler’s further west, where the Sand Vein ore is very thin (6 in. to 8 in.) and where it is claimed that the Ore sandstone only 40′ thick is separated from the Danville ore-bed by 20′ of slate.

Chestnut Ridge, to the south, in Oliver and Bratton townships, shows a double outcrop of the Ore sandstone and Sand Vein, and in its central portion carries a small amount of the Iron sandstone, a still lower member of the Clinton formation, on the crest of the anticlinal. It is completely gapped by the Juniata river about 3 miles east of McVeytown, where the Ore sandstone on the east side of the river is well exposed on both north and south dips of 20° and 25°. On the west side of the gap the river has eroded the north dip and outcrop for nearly half a mile; but the south dip was at one time extensively developed by Mr. C. Dull for nearly a mile west of the river. The old drifts and outcrop workings are all abandoned now. The ore was of good quality and occurred in a bed from 12 to 16 inches thick, dipping from 25° to 35° towards the south. The ore here was largely hard fossil and the breasts were never much over 20 yards in height. Between the river and Strode’s Mill run the openings are much more numerous.

The Bremen, Bortle, Brower and Aurand mines were all located in the south dip of the Sand Vein, which has been stripped at the surface through nearly its entire outcrop between Lockport and the river gap. Not a single operation was being carried on in this entire ridge during 1888; but common report speaks highly of the quality of the ore in the south dip of the anticlinal. It contained from 14 to 16 inches of ore, and the low dip (here decreasing considera-