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The outcrops vary in dimensions from such as have an area of 2 square
feet to one which is 35 feet long and in part 15 feet broad. All the outcrops
in this zone are alike mineralogically and consist of rust-stained magnetite
which on fresh fractures has a crushed or sheared appearance and may be
seen to hold considerable pyrite in scattered grains and ageregates of
grains. In spots the pyrite is very abundant and at one outcrop a zone ¢
foot or so wide is largely pyrite.

North of the zone of magnetite outcrops, higher up the hill-side and
at a distance of 40 to 150 feet from the zone, are five isolated outcrops of
altered porphyrite holding some magnetite and pyrite. Still higher on the
slope are two widely separated, small outcrops, one of magnetite, the other
of mineralized porphyrite. Two hundred and forty feet south of the zone
are two small exposures, one of magnetite, the other of magnetite adjoining
altered porphyrite.

The tunnel has been driven in the western part of the zone of magnetite
exposures and along a direction approximately at right angles to the trend
of the zone. In the open-cut at the tunnel entrance magnetite is exposed
on the east side for a length of 10 feet. In grain it varies from fine to coarse
and has a sheared aspect. In the tunnel for a distance of 29 feet from the
portal, magnetite appears on both walls. The magnetite is greatly fractured
and weathered, and much of it is low grade, being intermixed in a very
irregular fashion with altered country rock. Pyrite is abundant. At 37
feet from the tunnel entrance on the west side and at 41 feet on the east
side, the walls are wholly of altered country rock, the bottom edge of the
magnetite body having risen sharply so that the magnetite appears only
in the tunnel roof. At this lower contact of the deposit much pyrite is
present and the magnetite content is comparatively low. Beyond this
point for 28 feet to the end of the tunnel at 69 feet from the entrance, and
in two short crosscuts to the east, the walls and roof are of much fractured
partly altered rock, irregularly impregnated with pyrite and holding
here and there patches and small bodies several feet broad of magnetite.

ECONOMIC CONSIDERATIONS

The exposures of magnetite and country rock are too few to permit
of satisfactorily determining the size of the ore-body or bodies. The full
significance of the few, small, outlying exposures of magnetite and partly
mineralized rock is not apparent. But considering that similar mineralized
materials, though not in place, have been reputed to occur over a length of
4,000 feet, it is reasonable to suppose that more than one deposit of
considerable size is present. On the other hand it does not seem reasonable
to assume, ‘as has been done, that the several isolated exposures 250 feet
south of the tunnel and 110 feet below it, together with the outcrops of
the zone penetrated by the tunnel and the small, scattered exposures
higher up the hill-side, all belong to one ore-body. The outlying exposures
may be parts of important deposits, but if so, these deposits can scarcely
be continuous with the body or bodies partly exposed east and west
of the tunnel.

The six exposures in the immediate vicinity of the tunnel, the outcrop
at the tunnel mouth, and the magnetite exposed in the tunnel for a length
of 38 feet, presumably belong to one body of magnetite. The outcrops
occur within an area 140 feet long in a northeast-southwest direction,
70) feet broad at the southwest end, 30 feet broad at the northeast end,

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