Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/254

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226 F³.
E. V. d’Invilliers, 1889.

Naginney Upper Quarry.Limestone No. II.

Top Vein, Middle Vein
(Glamorgan flux).
H2O, 2.82 ― 
SiO2, 11.93 2.20 
Al2O3, 5.28 1.22 
Fe2O3, .30 ― 
CaO, 31.43 52.82
MgO, 10.87 .986

It is not known exactly from which portion of the extensive exposure at this quarry the samples were taken; but the results show in a general way the fact that both magnesian and fat limestone occur in the lower Silurian formation of the Kishacoquillas valley, in close proximity to one another, just as has been demonstrated by innumerable analyses in other parts of the state where the same formation occurs. In this special locality the middle portion of the exposure seems to be the best, and carries the least amount of silica and magnesia; but no casual inspection of the quarry exposed would enable the most careful observer to detect the different varieties of stone without the aid of chemical analysis, for which there was no provision.


The New Lancaster Valley axis maintains its strength fairly well beyond Locke’s Mills, carrying the slate of No. III on its back well into Union county. The valley is not travelled beyond Swartzell’s sawmill, and the exposures to the east of that point are very unsatisfactory and meager. Just east of Locke’s Mills the slates along the road dip N. 40° E., 10°–15° in Beatty’s knob, from which the rather gentle character of the anticlinal may be inferred.

From Locke's Mills down Honey creek the public road is always in limestone. Only one exposure however was seen, just beyond the first bridge, showing a blue slaty limestone of Trenton age, dipping about N. 15° E., 40° into the synclinal.

Leaving the forks of the road to Honey creek station, and taking the Milroy road, a beautiful ledge of limestone shows at creek level, dipping only 10°, N. 50° E. The slates in this trough extend to within a short distance of the road, and as the road turns north towards Naginney’s, the lime-