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The veins are known as the “ Blue vein”, “ Green vein”, and “ White
vein.” The Blue vein divides and one of the branches is called the “Jasper
vein.” The Blue vein, including the Jasper vein, has been proved to be
at least 700 feet long. Locally it is 10 feet wide, but its average width
may not be more than 5 feet. The Green vein may be an eastward con-
tinuation of the Blue vein. It is known to be at least 200 feet long, is
narrower in general than the Blue vein, but in a brecciated and branching
part is 20 feet wide. The White vein is not certainly known to be a single
lode as it is exposed only in a few places. It may be 500 feet or more
long, in one place it is more than 10 feet wide, but the average width is
much less. This vein is not well exposed between the end open-cuts.

The veins have numerous branches which appear to die out or pinch
to stringers within a hundred feet of the main vein. The eastern part of
the Blue vein and its apparent continuation, the western part of the Green
vein, consist of vein branches and stringers in brecciated rock. This may
be due to a local difference in the intensity of fracturing or to a difference
in the type of rock traversed by the main fracture zone.

The chief minerals are chalcopyrite, pyrite, hematite, magnetite,
arsenopyrite, quartz, jasper, and barite. Hematite, magnetite, and
arsenopyrite are uncommon except in local areas. Quartz is more plenti-
ful than jasper or barite, but country rock makes up most of the gangue
matter. Judging from surface exposures arsenopyrite is more abundant
in the Blue vein than in the others, but except for this feature all the
veins are much alike.

Metallic minerals make up about 20 to 50 per cent of the vein mat-
ter. Chalcopyrite is usually as plentiful as pyrite. Some channel samples
across the veins average 10 per cent copper and others show less than
1 per cent copper. Gold values vary from a few cents to $5 a ton. The
gold content is quite variable and appears to depend on the quantity of
arsenopyrite.

It is not known whether or not the width of the vein fracture is
related to the type of rock fractured. The branching parts of the Green
and Blue veins suggest that some such relation exists. As the beds of
rock are practically horizontal, any influence exerted by rock type will
find expression in long, horizontal ore-shoots or long, horizontal, lean areas.

RED TOP GROUP

The Red Top group is on the north side of Upper Bear river opposite
the George Copper group. The mineral showings were discovered many
years ago and have been developed in a small way from year to year.
The development work, consisting of two adits 200 and 300 feet long and
several open-cuts, has been done on two main mineral deposits, one being
a chalcopyrite-bearing replacement deposit and the other a vein of the
silver-lead type.

The rocks traversed by the vein are tuffs and lava flows of the Bear
River formation striking northeast and dipping gently northwestward,
and cut by several dykes. Some of these dykes on the Red Top group
and farther west can be followed for distances of over a mile and vary
very little in width.

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