The Butte daily miner. [volume] (Butte, Mont.) 1885-18??, 1886-01-01
The Proud positien New 8sla b. Butte %
. Mining Center.
A General Description Of the oeoloei.
cal Formation Of the Region.
Classlaostlon Of the vesns-The Coudf.
ton Of the Mlnos-The prospect
Of the Failure.

The recently issued volume al the United
States Geological Survey, upon 1.-THE
Mineral Resources Of the United States"
an advanced copy Of which was furnished
us. in order that its contents might be
utilized for this special edition, gives the
following exhaustive description-zeoloRi
cally-oi this camp:
The high position that Butte. Montana,
now occupies as q producer OF the valuable
metals, standing Second only to Lake
Superior in it's. shipments Of copper, and
ranking among the first in it's production
OF silver, has naturally attracted much
attention among those intereated in mines
and metals. Several valuable articles have
appeared in certain technical journals de-
scriptive Of some OF the individual mines
Of this district. but have yet to learn Of
the publication al any general descriptive
paper. giving an idea Of the geology Of the
camp, the peculiarities of it's veins, and q
trustworthy description OF the methods|em-
ployed for the treatment OF it's ores. The
object Of the present paper is to partially
hi this gap; and il it IL noticed that less
attention Is paid to the three or four great
silver mines and mills that first gave Butte
its celebrity than their Importance would
seem to warrant, it is because exactly this
subject, to the exclusion Of nearly all other
interests, has received particular attention
In the articles already mentioned, and be-
and Moulton mines and mills are accessible
to all.
.0.......#m THE DISTRICT. .48.a.
That portion Of the Butte camp which to
the present time alone possesses especial
interest to the miner may DO mostly In
closed within the lines OF q retangle having
q length Of 2h miles and q breadth Of mile,
roughly speaking. This retangle extends
from Yankee Doodle Gulch ON the
East to point somewhere below the Bos-
ton and Colorado Concentration on the
West, and from the Northern extremity
OF Walkerville district on the north to the
extension OF Park street on the south.
Within these narrow limits are the three
great silver mines already mentioned, the
Anaconda. Parrot, Colusa, Bell. Liquida-
tor, Gagnon. Saint Lawrence, Mountain
View, Clear Grit and dozens of other Noted
and productive mines. besides the whole
system Of silver-bearing manganese leads,
and an almost indefinite number Of veins
already discovered, and more or less de-
veloped. Outside this small area, though
there is NO lack Of prospects, some OF which
promise exceeding we'll, do not know OF q
single property which can yet (autumn OF
1850 be classed among the paying mines.
The geology OF this rich metalliierous
rectaDgle is at first glance exceedingly
simple. consisting apparently solely OF q
| coarse grained and q very hard granite,
containing an undue proportion Of quartz
and mica. and less feldspar than is usual.
On closer inspection it will be noticed that
while in the eastern or cupriferous portion
Of the area mentioned the granite Is exceed.
ingly coarse grained and shows no sign OF
stratifcation, in the western or arRentiier-
GUS division the mica predominates, and is
arranged to greater or less extent in par.
allel layers, approaching a mica schist.
So far as my observations extend, the field.
spar is entirely ortbuclase while both the
white and brown varieties Of mica (biotite
aud muscovite) occur, though in widely
varying proportions at different points.
There IL . regular and we'll marked
connection between the structure
Of the granite and the contents OF the fie.
sures by which ii IL traversed; but neither
the scope Of this paper nor the observa-
tons at my disposal warrant any further
speculation in this direction. 35%t
The miners universally speak Of purphyry
dikes, which run parallel with, and usually
from the wallsoi, all the large copper veins
that have been opened to any great depth,
But In every instance where / have been
l ah1N In na{s,a khn Aknv A..