The Anaconda standard. [volume] (Anaconda, Mont.) 1889-1970, 1899-08-06

in the Barker mining district. In the
| Judith mountains, north of the Maiden
| mining camp, there is a limited amount
Of magnetic iron ore. together with a
| mass of bog ore Uimonite.)
| From the general study made of the
| region it is evident that no general lead
| extends across the mountain, but that
| lenticular bodies of ore occur at the
contacts of many of the masses of
igneous rock. They were observed on
| Woodhurst mountain, on Iron creek
! a branch of Lion gulch. north of Yogo
| on the mountain top above that place.
and on Thunder mountain. Iron float
| was observed at other localities, and
| there seems little reason to doubt that
| it is of common occurrence about most
| of the larger igneous intrusions
THE Woodhurst mountain deposits
have. so far as known. been prospected
only on the southeastern flank of the
| mountain at the head of a small drain
age tributary to Galena fork of Run
| ming Wolf creek. The deposit has
been opened by surface cuts, exposing
| continuous mass of hematite in a
trench 40 feet long, cut at right angles
| TO the contact and hence across the
| lens. 1t lies at the base of a projecting
| tongue or offshoot of the porphyry
! body of Woodhurst mountain, and is
quite clearly a contact deposit. The
ore is strongly magnetic and evidently
the hydrated oxides of iron.
"A lens ~ feet thick of quite pure
hematite was observed on the noun
| tain ridge east of the head of Skunk
creek, near Yogo. The deposit occurs
al the contact between limestones and
a dark-colored, coarsely graduated
| rock (shonkinte.) On the north side Of
Thunder mountain, at the head of Iron
creek and an altitude of 5000 feet. the
contact between the porphyry and sed-
| imentary rocks is marked by lenses Of
| iron ores. The sedimentary rocks are
locally baked and metamorrhosed, the
| soft mica ceous cambran shales being
| changed to hard, flinty hornstones. The
| iron ore is in part, at least, replace
| ment of these rocks and occurs be-
| tween them and the granite porphyry.
| The ore is in lenses varying from few
| feet to 20 feet in thickness. but whose
| lateral extent is not exposed by out
crops or by the artificial openings thus
| far made. The ore is at present exposed
| in an open cut. and the quantity APP
pers to warrant mining If there should
arise a demand for such ores, since the
| ores could be easily transported by
| some gravity system to the railroad.
| From the analyses it would appear
| that the ore is fairly pure limonite,
| mixed with little quartz, but the ore
| is magnetic, and hence must be mix
| ture of magnetic with linlonite de-
rived from it. Openings along the con-
| tact on the southern side of the noun
tailn also showed iron ores.
In Fergus county the Judith noun
| tains, which rise so abruptly from the
| open plains country of the central por-
| ton of the state, exhibit large amounts
of bog iron ore, deposited apparently,
| from spring waters. There are also
| small contact deposits of the usual
mixture of magnetic and limonite. In
the neighboring Moccasin mountains
deposit of considerable magnitude was
observed by the writer. 1t occurs at
the contact of the lacolithic mass of
porphyry, which has been intruded be-
tween the sedimentary beds and lifted
them up as a broad dome. This ore is
also magnetic.
In jefferson county several deposits
of iron ore occur at localities favorable
for working. The largest is that found
at the west base of Jack mountain,
! where the bright-red ore forms a. small
butte rising above the general slope.
Near Elkhorn, on the summit of the
| peak by that name, there is large
| body of magnetite-limonite ore that is
| extensively opened by surface cuts. The
| mine is accessible from the railroad by
a graded wagon road about six miles
long. and all downgrade from the
workings. A few carloads of ore have
been shipped, used, it is understood,
as fiux by the silver smelter. The ore
appears to be a contact deposit be-
| tween andesite and granite with the
Sedimentary rocks.
On Fox mountain, west of Bernlce
station on the Great Northern railway,
a deposit of iron ore has been opened
by prospect trenches and shallow pits
The property is commonly called the
Calvin mines, three and a half miles
west and at an elevation of about LOO
feet above the railway, and is accessi-
4 to,
sintery or stalactitic botryodial forms;
it is not magnetic in the specimens
seen, and it gives a brown streak
Samples of the ore have been asSayed
and analysed, with the following re-
suits: Silica, 6.36; oxide of iron, S6.O7,
lbs.
THE small amount of antimony re-
ported as metallic probably occurs as
antimonite of iron and is of very rare
occurrence in ores of this class. The
assay value is as follows: Gold, oil
ounces per ton, $500; silver, 1.1s ounces
per ton, 70 cents; total. 1892.
"In Meagher county, ferruginous
sandstones, associated with lgnites, on
Warm Springs creek, were quarried for
fuxing for a short time. They are too
silliceous to be valuable. In Beaver
head county iron ore has, it Is said,
been extensively mined for many years.
In Cascade county carbonate ore oc-
ours interstratifed with the shales of
the coral formation dover cretaceous),
but do not occur in workable deposits
They are noted and analyses given in
the Mineral Resources for 1888, p. "a.
1.-THE iron ores of the state have thus
far been used only as a f1ux for silver
smelling, no pig iron being made. The
production credited to Montana in the
eleventh census report, 1889, Is 24O72
tons. 1891 the production was $685. tons
OF red hematite and 1900 tons of brown
hematite, which decreased to 4 300 tons
of red hematite and 2,17O tons of brown
hematite in 1892. In next year the pro-
duction has been grouped with the
other states in the figures published
by the office" HOSFORD
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