White Pine news weekly mining review. [volume] (East Ely, Nev.) 1910-1920, 1913-03-09
RELATIVE To RED
METAL OUTPUT
PORPHYRY MINES FURNISH THE
REAL COMPETITION N COPPER
PRODUCTION IN THE UNITED
STATES.

AlaAa61A - a
ton of the Calumet and Heela Mining
company who as an economical op-
orator is ~outranked by few. If any, in
the field of copper mining, has pre-
pared some very valuable statistics
bearing on the cost of producing cop
per in the various important districts
in the United States. He says:
1T is interesting to compare the
results obtained in the copper mining
district of Michigan. with those of
other parts of the country. and for
convenience the various groups of
mines may be classified as follows:
The Michigan group, consisting of
the copper mines in the upper
peninsula of Michigan: the Montana
group, consisting of the copper mines
in and around Butte; the porphyry
group consisting OF the porphyry
mines OF Utah, Nevada and Arizona,
and Mexico.
The most recent statistics avail
able are those for the year 1911. and
even they are o quite complete. but
the figures l quote owe a product of
approximately 100000, 600 pounds
of copper for the four groups men
toned out of a total of about 1900
IO00, 600 pounds produced and import
ed into the United States for that
year. Comparing the yield per ton
of rock or ore treated we find that
the Michigan group gives an average
of twenty and one-quarter pounds per
ton; the Montana group sixty-one and
three-quarter pounds; the porphyry
group about twenty-five pounds and
the southwestern sulphides seventy
four and one-half pounds.
1T would be extremely difficult to
make a comparison of the amount OF
work expended in mining and mill
ing the average ton Of rock or ore in
each of these groups, but it would
seem that on account of the depth
and the narrowness Of the lodes.
the Michigan district would afford
the most difficult mining. Montana
would undoubtedly come next, with
the southwestern sulphides third. and
the porphyry mines last or the easist
TO mine by reason of their large
surface deposits permitting in most
instances the use OF steam shoyels
and the shallowness and extent of
those deposits that are worked by
underground methods.
During the year 1911 the total
average cost per ton treated in each
of these groups was as follows:
Michigan group, s1.s6; Montana
group. 1874; porphyry group, sag;
southwestern sulphide group. IS. 1t
should be borne in mind, however.
that in the Montana porphyry and
southwestern sulphide group quie
large values in precious metals are
recovered, which values are credited
to the cost of producing a pound of
copper; whereas the value of
precious metals recovered from mines
in the Michigan group is almost
negligible. In the Montana group for
instance, the precious metals OF the
year 1911 amounted to 3.26 cents
per pound of copper produced; in the
porphyry group the precious metal
value was us per pound Of
copper produced, and in the south
western sulphide group III cents.
Applying these credits We have
the following comparison of the net
cost of producing a pound of copper
by groups: Michigan. 9.19 cents;
Montana, ga cents; porphyry, 7.9S
cents; southwestern sulphide. SOB
cents. From this it can be seen that
if it were not for the precious metal
values in the other groups, the Michi-
gan group would be the lowest cost
producer; or in other words, If the
comparison is made on the basis of
copper alone and no credit is given
for the precious metals recovered. the
results would be as follows: Miehi-
gan group. 9.19 cents; Montana
group. 1870 cents; p~orphyry
group, 1915 cents; southwestern
sulphide group. 1925 cents. The av-
erage net cost of producing this
pound of copper is s.96 cents. Michi-
gan. Montana and the southwest sui
phide averages are slightly in excess
of this figure, which indicates that
the real competition in copper pro-
duction is furnished by the ~porphyry
mines.
1T has been argued that the costs
published by some the porphyry
mines are not wholly correct mas
much as certain changes such as