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The shear zone in which the vein lies is several times as wide as the
vein and has not been thoroughly explored. Further exploration may
result in the discovery of wider ore-bodies. As the dyke follows the shear
zone, ore and dyke will in general be together, but the dyke may depart
from the shear zone, whereas the ore will remain within it.

Two large, parallel, quartz-barite veins, each over 10 feet wide, con-
taining disseminated galena, outcrop a short distance above the workings,
but have not been exploited. Several, small, rusty areas visible near the
shaft are local concentrations of pyrite and pyrrhotite in a bed of tuff.

KEYSTONE AND MORNING CLAIMS

The Keystone and Morning claims are in the valley of American
creek a short distance above its mouth. The country rock on the Key-
stone is argillite striking north and dipping 45 degrees west and on the
Morning is calcareous tuff. On the Keystone, open-cuts made many years
ago extend for a distance of 1,000 feet. The open-cuts may have formerly
traced a vein, but are now caved and do not expose vein matter. A
short adit has been driven along the vein at the most northerly exposure.
Here the vein is 2 feet wide, lies parallel to the strata, and consists of
quartz containing fragments of argillite and sparsely mineralized with
galena, pyrite, and chalcopyrite. In a shallow shaft 800 feet south of
the adit, along the line of caved open-cuts, a vein of similar width, which
is probably the same one, contains galena, sphalerite, chalcopyrite, and
pyrite. The vein was seen at only the two places and in those places was
not of commercial value.

On the Morning claim two short adits have been driven on a shattered
zone in calcareous tuff. Pyrite is disseminated through the rock, but
valuable mineral is rare.

RUBY SILVER MINES, LIMITED

The property of the Ruby Silver Mines, Limited, is located on
La Sueur (or Mosquito) creek which flows into Bear river just above
the mouth of American creek. The property was visited by Mr. Osborne,
field assistant, from whose notes the following account is. derived.

The country rock consists of black argillite with grey bands of quartz-
ite, and is intruded by a dyke that follows the bedding. The rocks strike
north-northwest and dip steeply northeastward. The mineral deposit is
a quartz sulphide in contact with the dyke. An adit at an elevation of
1,250 feet has been driven for a distance of 190 feet southeastward along
the vein. The vein is 3 feet wide near the portal, but narrows rapidly
and pinches out near the face. The mineralization is pyrite, galena, and
sphalerite in a gangue of quartz and calcite.

Properties West of Bear River

INDEPENDENCE GOLD MINING COMPANY

_ The holdings of the Independence Gold Mining Company are on
Fitzgerald creek. Most of the exploratory work has been done at an
elevation of 3,000 feet. The mineral deposits are situated along the zone
of dykes previously described as striking southeast across Bear River ridge