The Challis messenger. (Challis, Idaho) 1912-current, 1923-06-27
Railroads Lacking

The county has only 30 miles Of rail
road, where the Maekay branch extends
that distance over its eastern border,
but it is possible that within a few
years this branch viii be extended 70
the famous Sawtooth Park country at
the head if Salmon river, where plans
are already well advanced for a stupen-
dous engineering development involving
two storage reservoirs of the Arrow
Rock type and capacity, and 20 miles
of tunneling through the Sawtooth
range to divert the water of the upper
Salmon river into the Boise drainage
for the irrigation of half a million acres
of very fertile land lying between Boise
and Mountain Home.
Mackay, the present railroad terminus
in the county, is its most active min
ing center at this time, and its geology
has some points Of economic advantage
that have as yet been hardly appreeiat-
ed. The chief mining operation at this
point is that Of the Idaho Metals Co.,
formerly Empire Copper Co.
Idaho Metals Co.
This property shows a contact meta
morpbie copper deposit with an inter
esting history and promising future. Il
occurs on q high spur of the Sawtooth
range az an elevation Of 5000 feet and
its main workine<S,are equipped with
an aerial tramway, three and half
miles long, to the railway a. Maekay.
The deposit consists of a mineraized
zone 500 feet wide and mile long, at
a contact between a boss Of eruptive
granite or quartz-monzonite and a
series of massive sedimentary forma-
tons, mostly pure limestone 10000 feet
thick. The property has been developed
by adit and cross-eut tunnels TO a maxi
mum depth of 1900 feet attained by
the lower Cossaek tunnel. 5000 feet
long. It's production TO date has been
largely from above the 9OO-foot level
and has totalled upwards of 100000
tons of crude shipping copper ore, car
-ying values Of 1 to 10 per cent copper
and a uniform associated value Of rs
cents gold and silver 10 each unit of
copper. The ore was largely oxidized
down 70 the 7O0-foot level, but its
highest primary sulphide peak came
within 800 feet of the surface. The
primary sulphide ore is almost exclu-
lively fine-grained chaleopyrite, with
/ conspicuous absence of pyrite, whiea, |
however, has recently shown MP in fine |
ubie determinations at the 1,6e0-foot |
evel. The best sulphide ore develop |
nent of the property is now being OBJ
aimed through winze shaft sunk from
he 70O-foot level, that is 500 feet deep, /
nd from which two extensive levels 1
ave been driven and some large bodies
f sulphide shipping ore opened up con-
aiming an interesting increase in gold
alue.
Half Million Tons Exposed
This property has been worked on
he leasing system for the past fifteen
ears, employing about one hundred
len. In order TO hold the crude ship
ing ore values above 1 per cent cop
r, large reserves of ore in fills and
illars and outside dumps have been ex-
osed and accumulated, now estimated
I 100000 tons, above the 900-fOot level,
arriving approximately ? IL per cent
opper and $500 gold and silver per
on. For future treatment of these
ulphide ores, which, with the high
rade bodies now available, can be
weetened up to 8 per cent average,
milling tests have recently
cen conducted by the General Engin-
ering Co.. of Salt Lake, whose results
how recovery of % per cent of the
ombined values by straight primary
citation methods. A milling plant of
90 tons daily capacity, to be con-
tructed at the foot of the tramway on
he railroad, is being designed and It
J the hope of the company to have it
nstalled and in running order by next
all.
Mackay Lead Belt
Immediately north of the Idaho
fetals Co.'S. big copper deposits is
nick series of alternating pure and J