28 The American Geologist. July, 1893 
The third noticeable type of rock has been termed the Ox- 
ford type. It is named from a prominent locality at the Ox- 
ford tunnel on the Delaware, Lackawana and Western H. H. 
This rock is much coarser-grained, generally, than the Mt. 
Hope rock, and, in fresh fractures, has more of a bluish cast. 
The feldspathic constituents of the rock are about the same 
as the Mt. Hope type. There is hardly a trace of magnetite 
present. This with the characteristic presence of hornblende, 
makes it easily distinguished from the Mt. Hope rock. In 
addition to this the rock is beautifully and strikingly banded 
or foliated, which serves as a still further distinguishing 
characteristic* 
The above review is necessary in order to bring out tin- 
writer's point, viz., the striking resemblance of the magnetite- 
hearing rocks of the Adirondack mountains to those of New 
Jersey and southern New York. 
The writer visited the prominent iron mines of the Adiron- 
dack mountains while connected with the New Jersey Survey. 
and the following notes were made. 
From Carthage, N. Y., along the line of the Carthage and 
Adirondack K. R. to the Benson mines, there are frequent 
outcrops of the typical labradorite rocks of the Adirondack 
Mts. At Little river, the terminus of the road, is a remark- 
ably large deposit of magnetite iron ore. The ore body is 
lean, carrying from 15 to 25 or 40'/ of metallic iron. On ac- 
count of the size of the deposit, though, a great concentrating 
plant has been erected. The outcrop is reported to be three 
miles long and is about two thousand feet wide. This latter 
point was verified by the writer. 
The country rock in immediate contact with the ore hotly 
could not be found, if it showed on the surface, in the limited 
time for examination. The rock of the ore body, however, in 
its lower parts, had all of the lithological features of the Mt. 
Hope rock in New Jersey. The ore itself had the character- 
istics of the New Jersey magnetite. Molybdenite was sparingly 
found. Grains of phosphate of lime were also distinguished. 
Garnet in small crystalline grains was observed. 
* For a fuller description of the relations of these rocks to each other 
the reader is referred to Ann. Rep., State (Geologist of N. J., 1889, p. 34, 
et seq. 
