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bodies. The veins apparently tend individually to extend for distances
measurable in hundreds of yards. Along their courses they locally may
expand to several times their breadth elsewhere and they may hold this
increased breadth for hundreds of feet.

In addition to the vein-like bodies of magnetite, the mineral also
occurs in small areas of a few square feet consisting of country rock traver-
sed by seams of magnetite and in some cases accompanied by masses of
magnetite ranging in size up to such as measure several feet or more in
breadth and length. In some instances the country rock of these small
areas has been altered so greatly that few of the original constituents
remain. The exposures of these impregnations are small and isolated;
their relations to the veins was not directly established, but it seems entirely
probable that they and the veins were formed contemporanecously.

The parallelism displayed by the veins of each local area and their
westerly course in general, all of which is again exemplified 6 miles to the
west at Cherry bluff, indicate that the planes of weakness along which
the veins have appeared have been produced by an agent acting in a
uniform manner and over a considerable area, that is, presumably have
been produced as the result of the adjustment of regional stresses.

The veins have developed in a plutonic rock of monzonitic aspect.
Similar veins occur in similar rock at Cherry bluff 6 miles away and
reliable information indicates that analogous magnetite veins occur to
the southeast where similar or related plutonics have been recorded as
being present. If the magnetite veins are confined to the gabbroic
rocks, it may be that this association is merely due to the fact that these
plutonic rocks under the action of earth forces yielded the necessary
channels and sites for the magnetite solutions. On the other hand, the
apparent close association of the magnetite veins with these plutonic
rocks may also mean that the rocks and the vein-forming materials are
related in origin.

ECONOMIC CONSIDERATIONS

The magnetite deposits occur as veins of magnetite with a variable
amount of apatite locally developed in them. In addition there are also,
as on the Signal and Anvil claims, small outcrops showing magnetite in
streaks and veinlets or as grains and aggregates, disseminated through
the country rock or through much altered material. The veins developed
along parting planes which either before or during the period of filling wide-
ned, so that the net result was as if the magnetite had filled pre-existing
open fissures. The places where the magnetite does not occur in sharply
defined veins, but as veinlets or impregnations, may represent mineralized
areas that vertically or laterally grade into one or more magnetite veins,
but the general impression obtained was that the wider and more regular
magnetite veins are not directly associated with bodies of disseminated
magnetite. On the other hand since individual exposures of magnetite
impregnations seem to trend parallel with the general east and west direc-
tion of the true veins and since in the western part of the area of the Moose
claim, isolated exposures of magnetite impregnated material lie along
the prolongation of the strike of normal veins, it seems possible that some
of the impregnations do laterally or vertically grade into normal veins and
the impregnations may be valuable indicators of the existence somewhere
along the strike or dip of relatively wide and persistent magnetite veins.