Shape of the deposits. In shape the ore bodies show too much
variation to be characterized by any general term. On the surface
they appear as bands or stripes, and as indefinite patches ; the richer
ores usually occurring in rather sharply defined bands, while the
disseminated blende has an indefinite line of demarcation, shading
off into the country rock. The outcrop of the bands may appear
in narrow limits to have the regularity of veins with parallel walls,
but in a large way the ore pinches and swells and winds around
quite without rule. In one or two localities the ore seems to have
the form of a relatively thick lens or shoot.
The only satisfactory exposures of the deposits underground are
to be had in the mines of the Northern Ore Company at Edwards.
The body explored by the Brown shaft outcrops as a band of mixed
blende and pyrite with sharply defined and parallel walls. It is
about four feet thick at the surface, but gradually increases on the
dip and on the 200-foot level bulges out to fourteen feet after which
it again diminishes. It is still in evidence on the 500-foot level.
The longest drift on the ore body is 600 feet.
The form of the body thus appears to be an attenuated lens,
modified by rolls and pinches, while it is also warped out of plane
in a broad arc which curves around through an angle of 90** so that
the strike changes from northeast on the north end to northwest
on the south end.
The contact of ore and limestone in this deposit is usually sharp
and distinct, without any real gradation from the one to the other.
