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

l. Prichard slate .............. 5000
Archean complex.
The whole area OF the Occur
d'Alene mountains is broken, intense
Nv fractured and faulted with many
major dislocations and practically
;nnumerable minor requirements. AS
instances of the more extensive faults
are the Osburn fault, Dobson fault
White Ledge fault, McComber fault
Murray Peak fault, Big Creek fault
Ucelly fault, and Alhambra fault
ranging in lengths from or miles
to 30 and 40 miles and having maxi
mum throws ranging up to more than
one mile.
A striking popularity Of this highly
mineralized region with almost
countless faulted and non faulted fs-
sures is that comparatively very few
of the assures are vein filled at or
near the surface--the vast majority
of them being tight" or open for
fraction of an inch and empty or NIL
ed at intervals with a thin film OF Vein
quartz and perhaps accompanying
metallics, or very often, If intensely
faulted, filled simply with clay gouge'
Evidence appears on every hand that
these assures were formed under con-
ditions tending to squeeze at least the
upper portions of the assure walls to-
gether. The dominance of compress
i've stresses is further evidenced by
parallelism and the intimate assocla-
ton of assuring shearing, and schis-
tosity and is emphasized by an I'M
usual number of reverse faults Such
geologic structural phenomena are the
general result of moderately up
arched area sagging, subsiding, or
falling in" and suggest assures wild
err at the bottom than at the top, The
extremes of altitude above sea level IN
this district are 2150 feet at Lake
Occur d'Alene and 1926 feet for Stew
ems peak. The altitude of the town
OF Murray, located about the center
of the gold tungsten belt is 2772 feet.
The gold tungsten belt is found
wholly in the Prichard slate, and is
roughly circular or oblong area with
its slightly longer axis lying north
south and, in as far as traced, en-
braces the equivalent of circle about
IA miles in diameter.
The gold tungsten bearing veins in
this area may be classified in three
general systems:
/. Fissure veins trending norther-
ly-southerly.
2. Fissure veins trending easterly-
westerly with prevailing tendency
toward southeasterly-n orthwesterly.
3. Lateral veins locally called bed
veins, but the term bed" is more pro-
perly applicable only to sedimentary
notwithstanding the lack OF
precision in scientific thought evinced
by its careless use in professional pa
per 81, u. s. geological survey.
The fissure veins, sometimes called
yerticals in distinguishment from the
lateral veins, are usually approxim-
ately vertical, or of steep dip, and cut
the sedimentary strata. While II
would be no stretch of the imagina>
ton to say that the assures in the
gold-tungsten belt are so numerous
that one could stand at any assure
and throw stone to the next fissure
vet owing to the conditions above ex-
pressed in the fourth paragraph, COM
paratively few of these assures are
vein filed, at least, at the surface
The veins of the three systems are o.
thickness varying from few inches
up to and feet and more. Devel'
opments heretofore made in the dis
trict however, have been chiefly up
on the third class, the laterals, Whicf
are, perhaps, the more numerous or
at least, more easily discovered thai
the vetricals though the latter bea
some evidence Of possible superio
richness with values more evenly dis
tributed. Nevertheless, about nine
tenths Of the gold production hereto
fore made in the belt is assignable t
the lateral veins.
The vein filling in the three ven
systems is substantially identical, blu
exhibits tendency toward the NOR
uneven distribution Of values in tn
laterals. The gangue is white quartz
The chief minerals and metals carrie
are gold, silver. scheelite, silver sui
phides, iron sulphides, magnetic, sid
erite, tellurides and subsidiar
amounts Of chalcopyrite, sphalerit'
and argentiferous galena. In tn
manner Of distribution of mineral
and values extreme irregularity Is tn
rule. The ores vary from pure whit
quartz carrying free gold to almos
solid sulphides with usually high goi
content and little or no quartz A
illustrative of the irregular distribu
ton OF gold values It may be state
that in every vein mined to any cor
siderable extent numerous pockets
gold have been found carrying fe
hundreds to several thousand dollal
per pocket. Many small shoots OF o.