The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1917-04-05

larger extent have been mined carry
ling from 500 to $500 per ton and
many still larger shoots. say from 200
to 500 feet long, from 81 to 800 per
ton. The district has been long aban-
doned, and in early days, under diff
culties with which miners had then to
contend, ores running under 81 per ton
could not be profitably mined and
treated, but there are large bodies of
ores in the veins running between 81
and 81 per ton. 1t is estimated that
in early day milling not more than 40
per cent of the gold values in the ore
was saved on the average and as the
ores became baser in depth even the
small portion then savable near the
Surface rapidly decreased though the
contained values remained substan-
TALLY the same in depth.
Secondary enrichment probably does
not exist in the lateral veins and no
tangible evidence of it has been found
in the verticals. The deepest work.
ings in the district show ores at
depths of equal values to those nearer
the surface. The climate is humid,
the country covered with soil and
vegetation, and oxidation is found to
extend only to comparatively shallow
depths except along porous water
channels along the veins. Sulphide
ores are frequently encountered with
in rs feet of the surface and occasion
ally at grass roots.
Irregularity in distribution of the
tungsten minerals is the rule the
world over and no exception to the
rule is found here. This district has
never been prospected for tungsten
minerals-all the scheelite so far
found here has been incidentally
found in gold mining and in the gold
veins and placer mines. 1t occurs in
zones of scattered deposits, punches,
pockets, chunks, slabs, stringers,
| lenses, kidneys, veinlets and in dis
seminated form through compare
lively small sections. Such zones Of
tungsten mineral appear always to
have their longer axis on the dip,
never on the strike. While the deep
est shaft beneath the surface is about
900 feet on the dip no bottom has yet
been found to the scheelte zones in
this gold tungsten belt. In the early
day. mining scheelite was unrecogniz-
ed by miners and allowed to go to
waste.
| opened to any considerable extent all
| the metals and minerals above named
have been found and found in the
manner of distribution of values
herein set forth.
The structural geology and dynam
| les of this gold-tungsten area, as well
as the neurological character of the
ores, Enthusiastically predicate the der
ivation of the ores from considerable
depth by ascending thermo- mineral
laden solutions through the vertical
| assures and under enormously high
pressure. The lateral veins are lat
eral to the vertical feed assures and
| lie parallel to the planes of stratifca
ton in the Prichard states. Though
NORMALLY these lateral veins would lie
horizontal and extend out nearly or
quite at right angles to the verticals,
they are now commonly found tilted
| to shallow dips, less than As degrees,
along with the enclosing states. The
Prichard states are most commonly
dark blue argillte with individual
strata from to 20 inches in thick
ness. The pressures exerted upon
these mineral laden solutions were
sufficient to force them into and along
the bedding planes and lift the super
cumbent country height commen-
surate with the thickness Of the lat
eral vein. The mechanical process Of
formation of the lateral veins was not
unlike that of igneous stills. 1t Is be-
lleved the lateral veins were formed
prior to the reformation of the sedi-
mentaries. They are now faulted
with the country at very frequent in
lteryals, and have plainly been sub
tjected to all sorts of local disturb
ances. AS is frequently the case with
So called blanket veins these lateral
lveins extend through large areas ow-
ling their extent largely to the great
number of feed assures favorably
distributed. These lateral veins are
mot infrequently traceable for thous-
lands Of feet. There is good evidence
for believing that at least five of
these lateral veins underlaid the gold
tungsten belt-segments of them have
lsince been carried away by erosion.
The extent of the lateral vein was de-
pendent upon the number, situation
land productiveness of the contribut-
ling vertical feed assures, the volume
os material afforded, the pressures en-
countered to the forcing the material
into place in the form Of a lateral
lvein. Often three or more of these
lateral veins are found on the side Of
la mountain separated by vertica
|spaces of 200 feet, or more, or less
There are occasional strata Of quartz
lite interpreted in the Prichard slate.
and quite uniformly quartzite STRAIT.
Inp, for,,,c tho vonf nv fIonN fnr Nh.