The Butte daily miner. [volume] (Butte, Mont.) 1885-18??, 1886-01-01

This grade OF ore forms the principal value
OF the camp, occurring with such regular
ity and in such large bodies that mining is
robbed OF most OF its risks. The tirst-class
ore is distributed with little regard for reg
ularity, in chutes, chimneys, pockets, kid.
neyH and every other conceivable form, and
on an average may constitute One-tenth
Of the entire ore. Where the various mines
differ SO greatly in both strength and quail
ity. it il difficult to give average figures
with any approach to accuracy. but think
] UNI well within bounds in placing the aver
age width OF pay ore in the principal copper
veins at feet. The Anaconda IN the widest
OF any yet opened, averaging certainly over
12feet Of profitable ore, and in many places
widening to 30 and 40 feet for a great dis.
tance. In order to show the unusual depth
which this erubescite ore attains in this
district, before being replaced by the poorer
yellow sulphides which doubtless form the
normal unaltered ore Of these veins, will
mention here that the SOO-foOt level Of the
Anaconda shows no diminntion in the rich
ness of the ore. III ! remember rightly. the
deepest point in Chill ut which these pea
cock ores have held was in the celebrated
Pique mine ut depth Of about 500 feet, at
which point the rich erlbescite ores were
replaced by yellow sulphides, averaging
about per cent. 1t seems probable that
Butte may count ON IL still greater depth
Of rich ores.) The Parrot and Liquidator
also carry exceedingly strong ore bodies,
and Ot remarkable continuity.
For convenience OF more minute descrip
ton, the copper veins may he ctLssed in
two subdivisions:
l. Those in which the copper il found
mainly in the shape Of copper glance, or u
mineral greatly resembling copper glance,
though not containing quite the amount Of
copper called for by the formula Gus.
2. Those veins in which erubcscite il the
OFinciOal conner. bearing mineral
The Anaconda and l4iuuidatOr are good
examples Of the first division, having. as a
rule. gangue rock of quartz and tlecom-
posed feldspar, and carrying scarcely any
other ore except copper glance and Il small
percentage OF pyrite, thus yielding concen-
class ore which il now sacked and shipped
to Europe, consists entirely OF high grade,
forming, both as regards quality and guam
tity, perhaps the finest shipping product in
the country. The Liquidator andC also
furnish a very large amount Of second-class
ore, which is sufficiently free from pyrite to
concentrate to 30 per cent and over, though
in the lower levels, as might be expected,
the proportion OF pyrite has increased.
The second division is represented in its
most perfect type by the great Parrot vein
and its eastern extension, and for some
1000 feet carries an almost uninterrupted
ore chute 80 far as explored. 1t is charac-
y
carrying nearly its entire copper contents
in the shape Of that mineral, the occurrence
OF copper pyrites being rare and unimpOy-
tant. The first-class ore can be easily Sc
lected to 30 per cent, while nearly the entire
vein. from to 80 feet in width, ia suitable
Tor concentration, samplins II per cent as
the average OF three years working But
it is not alone as IL copper vein that the
value oil the Parrot must be estimated; it
is also Il silver.bearing lead of great value,
carrying on an average two-thirds Of an
ounce of silver to each per cent Of copper,
while above the water line. to ~ depth of 80
feet or more, there is IL fine body OF free
milling silver ore OF great strength and val
ue left untouched.
The value ot nearly all these veins il con-
siderably enhanced by the fact that to a
depth OF 800 feet no serious amount OF
water was encountered, and where proper
appliances have been introduced, natural
ventilation sutfices to keep the air in II per-
fectly good condition, The country rock
il also Of such a quality that no difficulties
are encountered in timbering, beyond such
as naturally arise in working out an ore
body Of 30 or 40 feet in width, and which
supplies no barren material for filling.
THE SILVER VEINS.
The second great division VI veins in.
cludes the manganese silver group,
and presents certain unique features. In
speaking OF the formation and mineralogi-
cal characteristics of these leads, l am
fortified by the opinion OF Profnssor Alvin
Weisbach professor Of mineralogy at the
Freiberg School OF Mines, who examined
some OF the mines and ores OF this district
with me. These manganese veins all lie in
y small and strictly circumscribed territory,
to the west and north OF the copper group,
and most OF them crop boldly to the sur
face, forming often large comb.like ridges OF
brown and black rock, stained principally
by the oxides OF iron and manganese, and
showing every evidence OF thorough decom.