By H. S MUNROE.
(Continued from Vol XII., p. 27 )

Formation of Mineral-Deposits.
The engineer should, of course, be familiar with the literature
of ore-deposits, and fitted by practical experience in mining opera-
tions and by training in field geology to make an intelligent ex-
amination of the deposit. An admirable series of articles * on the
literature of ore-deposits has lately appeared in the Quarterly
to which the student may be referred, and which will serve as a
guide to a course of reading on the subject.
The engineer should not be too hasty in his generalizations, and
should bear in mind that similar deposits may have widely different
Origin, and even that parts of the same deposit may be due to dif-
ferent causes. Deposits of magnetic- iron in some cases may be
altered bog-deposits or metamorphosed beds of carbonate of iron,
originally of chemical origin; in other cases they may be purely
mechanical deposits concentrated by the action of running streams.f
or again in other cases, it is possible that they may have been
formed by replacement, or deposited from solution in cavities and
fissures. Or part of the deposit may be due to one cause and
part to another as at Iron Mountain, Missouri.^



 **()n the Literature of Ore-Deix)>its/' by J. F. Kemp, School of Mines Quar-
TERi-Y, vol. X., pp. 54. 116, 326; vol. xi., p. 359.*

t H. S. M., .School of Minks Quarterly, vol. iii., p. 43.
X The •• Iron Mountain Mine," Prof. W. B. Potter, American Institute of Mining
Engineers, New York meeting, September, 1890.
vou XII.— 9



Ii8 THE QUARTERLY.
