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The limestone band is cut off on the west by the granodiorite stock.
It is followed by natural exposures and a series of cross trenches for 1,450
feet in an east to southeast direction to where it ends along a fissured zone
near the top of a steep bluff at elevation 5,475 feet. The limestone
formation is lenticular in outline, attaining a maximum width of 65 feet
midway along its outcrop. Lens-shaped ore-bodies consisting of a
pyrrhotite-sphalerite-pyrite replacement of limestone occur at intervals
along the limestone horizon. The mineralization appears to be localized
to zones where small faults pass into the limestone. Recrystallization
and flowage have absorbed differential movement within the limestone,
so that fissures do not penetrate this formation beyond a few feet.
Consequently, the ore-bodies are commonly along the contact of the
limestone. The ore-bodies are short and lenticular in surface outline,
but may be pipe-shaped.

About 150 feet south of the easterly end of the main limestone band
there is a smaller body of limestone lying on the south side of a fault.
This mass is 60 feet wide where it borders the fault, but narrows and
ends 300 feet to the southeast. Midway along its strike it splits and the
southeast branch, ranging from 4 to 10 feet wide, runs down the north wall
of a small, steep ravine for about 150 feet. This limestone body is believed
to have formerly been an upward extension of the main limestone horizon,
and to have been downfaulted to its present position. At the contact of
the limestone with the fault there is a replacement ore-body that resembles
the pyrrhotite-sphalerite-pyrite type, but here the replacement minerals
include galena, arsenopyrite, and chalcopyrite. Northeast of the limestone,
where the wall-rocks along the fault are andesitic flows and interbedded
tufts, there is a calcite vein containing silver, lead, and zinc sulphides.

About 275 feet from the east end of the main limestone band there
is an outcrop of solid sulphides along the south side of the limestone at
its contact with green tuffs. The sulphide body is lenticular, 50 feet long,
and with a maximum width of 15 feet. It consists of solid sulphides,
there being about 40 per cent black sphalerite, 40 per cent pyrrhotite,
and 10 per cent pyrite. A shallow shaft is sunk at the centre of the
ore-body and about 20 tons of ore from the shaft is stockpiled. A grab
sample of this ore assayed: gold, 0-165 ounce a ton; silver, 1-30 ounces
a ton; zinc, 17-43 per cent; nickel, none.

At distances of 30, 45, and 60 feet, respectively, east of the 50-foot
sulphide lens trenches cut across the limestone disclose a heavily rusted,
oxidized zone 10 feet wide. About 140 feet farther east, near the east
end of the limestone band, there is an oxidized zone 12 feet wide exposed
in an open-cut near the top of a steep bluff. The oxidized zone erades
downward within a few feet to unmineralized limestone. It evidently is
merely fragments of rocks cemented by limonite derived from oxidation
of a nearby sulphide lens. A little farther down the steep slope the
limestone pinches out abruptly, and from its tip a sheared zone continues
down the slope. The sheared zone strikes east and dips 70 degrees
north. At elevation 5,375 feet an adit is driven 125 feet along this sheared
zone in andestic rocks, but does not disclose any mineralization. The face
of the adit is roughly 125 feet below the east tip of the main limestone