The Eureka sentinel. [volume] (Eureka, Nev.) 1902-current, 1909-06-12
Remarkable Success of
The New Windfall Mill
Extracting SO Per Cent Of the Values In lao Tons Per Day
and Requires Only Seven Men to Operate 1t

The Eureka district can now boast the most successful reduction
plant, from every point of view, that there is in the State of Nevada,
not even excepting the new mill of the Goidfeld Consolidated
Mines Company at Goldfeld, Nevada.
On the 9th Of this month the new mill Of the Eureka Windfall
Mining Company was started, and has been in continuous successful
operation since, treating lao tons of ore per day.
This mill marks a new era in the reduction of the ores Of the
Eureka district Heretofore the world has looked upon the ores
coming from this district as being smelling ores, requiring the
usual high treatment costs attendant upon this form of reduction.
When the Eureka-Windfal Mining Company took over the
property bearing its name, the Kaeding Construction Company, of
Goldfeld, Nevada, was called in to devise a process for the reduction
of the ore. After numerous tests by this latter company, they
recommended the construction of a reduction plant to depend
entirely upon the extraction of the gold and silver contents by the
cyanide process, disregarding what lead contents might be in the
ore, as the cyanide process will not recover the lead.
Other metallurgists were employed to make tests on the ore,
and some Of them rendered reports adverse to the method outlined
by the Kaeding Construction Company, but after much consideration,
pro and con, the process outlined by the Kaeding Construction
Company was adopted. The method in brief is as follows:
The ore as broken from the slopes is run over a grizzly which
takes out the pieces larger than five inches. Such pieces are
broken up and with the undersize from the grizzly are trammed
over a trestle $50 feet long and dumped into a receiving pocket
From this receiving pocket the ore falls by gravity to a large
revolving trommel, with screens of number three mesh. The under
size from the trommel falls into a receiving bin under the trommel,
while the oversize feeds by gravity to Gates crusher and from the
crusher to a set of rolls, the product after leaving the rolls falling
into the same bin as the undersize from the trommel. The entire
product has now passed the crushing machinery and is ready for
the steel teaching tanks, of which there are six.
From The receiving bin under the crushing machinery the ore
is discharged on to a belt conveyor which runs over the tops of the
teaching tanks. The belt, in transit, passes through an an auto
matte, selfpropellIng reversible tripper and this machine passes
back and forth over the tank to be filed, distributing the ore auto
matcally into the tank.
After treatment by cyanide solutions for "a hours, the charge
is washed and discharged through the bottom of the tank on to a
belt conveyor that delivers the ore to the waste dump.
The solutions containing the gold and silver values pass
through the gold storage tanks to the extractor house, where the
values are precipitated by means of zinc shavings.
In the extractor house are situated also the bullion melting
and slime mufHe furnaces, acid clean up tank and the vacuum pump
for drying gold shines and furnishing air to the sulphur burner.
The plant rs SO arranged that all the mechanical operations are
performed by machinery driven from a single 40 horse power gas
engine. This engine drives to a main line shaft, and the various
conveyor and crushing machinery drives are taken off the main line
shaft. The engine is fitted on one side with a rope drive sheave,
and this rope drive operates the counter shaft in the extractor
house from which are driven the solution pump. vacuum pump and
agitator in the clean up tank. Al. tanks are of heavy steel riveted
with pneumatic hammers.
J. J. Jones, the manager, says that while no false economy has
been pracsiced, nevertheless he believes this to be the cheapest
constructed plant of its capacity ever built in America.
The finished plant has cost less than $4,000. and this amount
includes items of roadwork and all costs chargeable to the mill
Owing to the fact that the mill was built in the
middle of Winter, with snow on the ground most of the time, the
construction cost has been remarkably low, and rebounds to the
credit of the II aeding Construction Company.
The milling costs will be lower than any reduction plant in the
State of Nevada, and the extraction higher.
At this time the mill requires the services of only two men on
each shift, with the mill superintendent on day shift, making a total
of seven men employed in the mill. George L. Kaeding, in charge
of the construction, believes that this small force can be reduced
after the men got into the swing of the mill operation.
At this time the mill is making an actual extraction of a little
over SO per cent of the gold and silver contents of the ore, the total
of these contents being about $50 per ton.
1t is to be hoped that the success of this mill will be an
incentive to the opening up of other mines in the section which have
quantities of ore susceptible of the same treatment
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