Gilpin observer. (Central City, Colo.) 1897-1921, 1916-12-28
PRODUCTION OF MINES
COLORADO OUTPUT OF GOLD IN
1916 DECREASES.
and Zinc Shown and Values In
crease Over $9,e34,0o0.

Washington.-The mine output of
gold, silver, copper. lead and zinc In
Colorado for eleven months of 1916,
and the estimated output for Deem
Der. according to data compiled by
Charles W. Henderson. of the United
States Geological Survey. Department
Of the Interior, indicates a yield for
the year of $1S.94O,0OO in gold. 1920
600 ounces Of silver, 70,200,000 pounds
of lead Tin terms of lead in lead bullion
and lead in leaded-zinc oxide). $780,
900 pounds of copper, and 130,000,00O
pounds OF zinc Tin terms of spelter
and zinc in zinc oxide), with total
value of nearly s49,OOO,OOO compared
with $22,414.944 in gold, 7,027,972
ounces of silver. 6S,S1O,597 pounds of
lead. 7,112,537 pounds of copper, and
104 ,594,994 pounds Of zinc, with total
value Of $43,426,697 in 1915. This
shows a decrease of nearly $3,475,000
in gold, but increases of $4,000 ounces
Of silver, 100000 pounds of lead. l.
$4,000 pounds of copper. and 25.000,-
900 pounds of zinc. With the increased
average value of metals the values
show increases of $1,451 900 for silver,
$1,540,000 for lead, $1.1O3,0O0 for cop
per. and $4,S40,00O for zinc.
The tonnage treated by the Globe,
Leadville, Pueblo, Durango and Salida
as in 1915, the ore coming from Cana
da, Colorado, Idaho, South Dakota, and
other state, and including a greatly IN
creased quantity of zinc residues from
Kansas and Oklahoma zinc smelters.
A flotation plant for the treatment of
zinc-lead sulphide ores of the San Juan
region was built and operated at the
Durango smelter during the year. The
copper mating plant at Ouray was
idle. The United States Zinc Com
pany's magnetic wet concentration
mill and smelter at Pueblo were &C.
lively operated on zinc-lead ores from
Colorado and other Western states.
The Western Zinc Oxide plant at
Leadville was operated steadily. The
Western Chemical Company's acid,
magnetic separation, wet-concentra-
ton plant at Denver was operated
steadily at increased capacity, as was
the Empire Zinc Company's 200-ton
magnetic separation plant at Canon
City, both treating chiefly Leadville
zinc-lead sulphide ores. The old Rocky
Mountain smelter at Florence was re-
modelled into plant for the treat
ment of zinc-lead-copper sulphide ores
as an intermediate plant for the River
Smelling & Refining Company's cleo
trolytic spelter plant at Keokuk, Iowa,
and large tonnages of sulphide ores
were received from various Colorado
counties. Copper ore, copper matte.
and cyanide precipitates were shipped
to the Omaha smelter, and some cop.
per and lead ores were shipped to
Utah plants.
The gold output of Cripple Creek
(Teller county, was $11, 800, 900, de-
crease of $1,SS3,OOO Development con-
tinued at lower depths with the con-
tinued gradual lowering of the water
level as the Roosevelt drainage tunnel
was advanced toward the Vindicator-
Golden Cycle properties. Experiment
tation with the flotation process was
continued by the indicator company
and the Portland company for the
treatment of low-grade mine and dump
orc.
The Golden Cycle cyanidation mill
at Colorado City, and the Portland cy-
anidation mills at Colorado Springs
and Victor, were operated steadily, but
with decreased output. The yield
from the small cyanide plants in the
Cripple Creek district was not so large
as usual.
Lake county, chiefly Leadville, but
including also the Lackawanna gulch,
Sugar Loaf and st. Kelvin lode dis