The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1915-09-23

the United States Zinc company add
ed 24O0 retorts at Sand Springs and
Is building 1900 more. The Kusa
Spelter company is building a smelte7
at kusa, a new town in a gas and
coal belt about FIVE miles east Of
IIenryetta. Five blocks of $50 re-
torts each are under active ~cnnstrue-
ton, and the company expects to have
1880 retorts in operation in September
and 1920 more in October. 1t is prob
able that on the completion of the
plant work will Immediately be begun
on another unit of the same capacity.
In Colorado the United States Zinc
company added 800 retorts to the
plant nea Pueblo and is building 800
additional retorts.
Total Smelter Capacity.
The total number of retorts was
1884 at the close of 1914 and 1870, 642
at the close of June, 1915, an increase
of 16, 1928 r~etorts, or Is per cent, over
the smelling capacity in 1918. The
whole number of retorts in operation
in June was about 129, 900. Since June
$50, 34,04S retorts have beer completed
Tor are under construction or in con-
temptation. If all these are con-
sstructed together with the $500 addi-
Itional at the Kusa smelter, the zinc
Icr1aIfipo n n oNaafFxr 80 KIo ao,YV1krry r-s1i
Ibe increased nearly SO per cent over
1914. These figures differ somewhat
from those given in the preliminary
midyear report owing to the inclu-
Dsion of later information. 1t seems
likely, however, in view of the recent
decline in spelter prices and the large
increase in capacity already available
that some of the contemplated addi-
Itions will not be made.
In 1908 the United States geologi.
cal survey instituted an inquiry to de-
Itermine the smelling capacity per re-
tort. The result of this inquiry gave
Az short tons of spelter as the maxi
mum output per retort with steady
operation.
The zinc content of ore smelted
ranges from about 20 per cent in some
Leadville %carbonates to so per cent in
Joplin blende. The spelter yield per
retort does not vary exactly with the
zinc content of the charge, for the
smelling loss is about constan Mt for
each charge. Hence, two charges of
80 per CEN zinc ore will show double
the loss of a charge of so per cen ore,
or probably more than double on ac-
count of the extra amount of foreign
material in the charge.
JopIin's Great Record.
During the period 1906-1908 about
So per cent of the spelter smelted in
the United States was produced from
Joplin high grade ores. In the last
few years only about 40 per cent of the
total has been smelted from Joplin
and owing to this more extern
siye use of lower grade ores the ca
pacity per retort must tend to be
somewhat lower than in 1908. Again,
owing to the large probable produc-
tion for the current year the high
grade Joplin ores will constitute a
still smaller proportion of the total
than heretofore; hence the average
output per retort will be lowered still
further. Another fact that tends to
reduce the average is that owing to
the unprecedented difference in price
between prime western" and high
grade spelter a considerable numb r
of retorts are employed in redistilling
prime western" spelter to improve its
grade, reducing by that much the na-
for smelling ore and hence the
average output per retort. These
facts are offset to a certain extent by
the improvement in zinc recovery
which must have taken place since
1908. 1t is plain, however, that an
exaggerated notion of the probable
output of spelter will result from null
tiplying the number of retorts by IA
tons.