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A peculiarity of the veins on the Porter Idaho is that they are deeply
oxidized. The ore as stripped commonly consists of rusty material con-
taining residual fragments of sulphide and quartzose matter. The sul-
phide is chiefly galena with some of the other minerals previously listed.
The lowest adit or No. 2 adit crosscuts the Wake vein at a vertical depth
of 275 feet below the outcrop of the vein and 450 down the dip from the
outcrop. According to samples from the vein at this depth the ore is still
partly oxidized, but more of the nature of the primary vein matter can be
discerned. Ankerite as well as quartz is here a common gangue mineral.
Sphalerite is more plentiful than at the surface. Arsenopyrite, chalco-
pyrite, and pyrrhotite are present in minor quantity, they may also occur
near the surface but were not noted in the material examined. Galena,
tetrahedrite, and silver minerals are abundant and ruby silver is more
abundant than in any of the material examined from near the surface.
Native silver was also found in one of the deep ore specimens.

_ Prior to the driving of No. 2 adit, although the veins were known to
be deeply and rather thoroughly oxidized, it was not believed that actual
enrichment had taken place. However, the ore from No. 2 adit, contain-
ing as it does abundant ruby silver and some native silver, lends weight
to the idea that some silver has been actually carried downward and rede-
posited at the base of the oxidized zone.

While No. 2 adit was being driven it was relatively dry until the Big
Rig fault was crossed. Beyond the fault all open cracks in the rock were
full of water and for some time the driving of the adit was greatly handi-
capped by the large flow of water. The fault gouge is apparently an
effective barrier, preventing the surface water from moving downhill
through fractures near the surface. It is quite possible that formerly the
surface water on the upper side of the fault found some deep outlet and
that surface oxygen was carried downward in this water and thus caused
the deep oxidation.

The development at the Porter Idaho mine consists chiefly of adits.
Two adits 100 and 150 feet long and one 20 feet above the other, have
been driven along No. 1 vein. Ore has been stoped between the lower
adit and the surface. A short adit has been driven along No. 2 vein, and
some ore has been stoped. Five short adits, 50 to 100 feet long, have
been driven on No. 3 vein. Ore has been taken from four of them. An
adit 150 long has been driven on the Wake vein, and ore has been
stoped. A short adit has been driven on the Winze vein and a shaft sunk
to a depth of 70 feet. A drift 250 feet long has been driven from the shaft
45 feet below its collar. Ore has been stoped from the vein above the
drift. All of the openings so far mentioned are merely about entrances
into the veins to facilitate the stoping of ore.

No. 1 adit commences as a crosscut on the hillside below the Big Rig
fault. It has been driven northward and encounters the Big Rig fault 250
feet from the portal. A drift at this point follows the mineralized and
crushed ground eastward for 350 feet and then turns north as a erosscut
and drift for 150 feet. The Winze vein is present in the drift to the east
and also near the north end of the crosseut and drift to the north. A
little ore has been stoped from the Winze vein and from the Big Rig fault