Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/261

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1869.]
TATE AND HOLDEN IRON-ORES WITH BASALTS.
159

Table of Analyses of Pisolitic Ores.


Constiuents. I. II. II. IV. V. VI.
Kilwaughter. Tully. Red Bay. Sliveanance. Sliveanance.
Peroxide of iron 45.00 45.00 59.40 77.22 71.00 81.50
Protoxide of iron 18.00
Oxide of manganese tr. tr. tr. 2.57
Titanic acid 2.00 tr. tr.
Vanadic acid tr. tr.
Alumina, soluble in acids 36.44
Alumina, insoluble 32-50
Silca insoluble 3-50 10.40 20.65 9.00 8.50
Silca soluble 0.50
Magnesia 2.44
Lime 0.56 0.35 .93
Water of combination 18.00 12.65 8.40 2.13 1.96
Percentage of metallic iron 31.50 31.85 41.58 54.05 63.70 65.20
Analyst J. Cameron. J. Cameron. Dr. Apjohn. J. Cameron. J. Cameron. Pf. Hodges.

The above analyses are of specimens selected as fair samples of the iron-ores ; the great variation is in a great measure accounted for from the samples having been taken from different parts of the iron-band. Numbers I and II. are of a mixed character, the others containing a greater percentage of iron according to the predominance of the spheroids.

IV.Nature and Origin of the Ferruginous Series at Ballypalidy.

1. Section at Ballypalidy.—The iron ochres of Ballypalidy, which are undoubtedly of sedimentary origin, will next occupy our attention. Though references have been made to a section of the iron-ore series at this locality in the pages of Society's Journal<r1, yet we are constrained to submit further observations on the succession of the beds there exhibited, inasmuch as incorrect impressions regarding the true relationship of the ores to the red bole or ochre-bed and to the lithomarge will be formed from a perusal of the sequence of the beds as given by the author of the paper referred to. Thus, in the section given on p. 358, the beds are enumerated in ascending (and not descending) order ; and at p. 361, the plant-remains are stated to occur in the red bole ; and, again, Mr. Du Noyer, in a paper read

  • r1 Vol. xxv. p. 357: W. H. Baily, "Plant-remains from beds interstratified with the Basalt."