The Anaconda standard. [volume] (Anaconda, Mont.) 1889-1970, 1899-02-16
Which Is Attracting the Attention of
New York Mining Men.

winch Is Attracting the Attention OF
New York Mining Men.
The Engineering and Mining Journal of
New York, in it's last issue, gives very
interesting description of the placer min
ing plant which is located at Virginia
City, and which is attracting the atten-
ton of Eastern mining men,. The article
is as follows:
"a new and interesting placer mining
plant is now in operat ton near Virginia
City, Mont. at the mouth of Alder gulch.
1t is owned by the Conrey Placer Mining
company. This plant comprises two exca-
vators which dig the material and deliver
| it into a hopper about 80 feet above the
ground. From the hopper the material is
washed by 10-inch stream of water
| thrown on it by centrifugal pump over
| grizzly, where the larger rocks and bould-
ers are separated from the finer material
which latter drops about five feet into the
! f1ume or sluice. This siuice is about 200
| feet long and has a grade of 5 per cent
! It is lined the entire length with cross riff
fes. which catch the gold as the water
washes the material over them, the bulk
| of the gravel and sand being carried off
| leaving the gold in the sluice. The gold is
gathered by amalgamation with mercury
| which is thrown into the sluice boxes at
| intervals; the mercury also sinks into the
| spaces between the rifles. The amalgam
|
the gold saved and the mercurial vapor
condensed under water. to be used again
| by the familiar method The waste ma
/ terial at the lower end of the siuice
is spoiled as convenient The entire hop
per and sluice being mounted on wheels,
| 1t is easily moved when necessary, in or
der to follow the progress of the eXca-
/ yators.
With this plant the cost of handling
i tn nj
mum, so that it may be profitably used
| to work old tailings or ground con-
| tanning values so low as to be unworka-
| BITE by the ordinary methods of placer min
ing. The most expensive part of the work,
the digging of the gravel and delivering
it in the hopper, is smpliied by the use
| of the eNcavators.
"These eXcavators are mounted on
skids or runners, moving over ties of 1Ox
| 10-inch tmbers, laid on the ground at
| right angles with the sllids. These skids
| carry the platform of the machine
which is "a feet wide by 80 feet long. Four
/ feet from the end of the platform the A
| frame, which supports the boom, is placed.
1t is So feet high and 40 feet on the base.
/ The boom is so feet long, and has a work
/ ing radius of 70 feet through about $50
degrees. The swinging of the boom and
| operating of the bucket are automatic
/ and controlled by one man located in the
lever house. This rig is not new, being
/ used largely upon land excavating ma
| chimes, but its application to placer min
ing is new and interesting and has been
| productive of excellent results in this in
/ stance.
1.-THE Hayward patent orange peel buck
ct of two cubic yards capacity is used.
/ The bowl of this bucket is divided into
/ four sections. or blades, thus making -four
| penetrating points. These are shod with
cast-steel points. This bucket is found to
/ fill itself and operate successfully WHEREBY
er the nature of the material and it's hard
ness will permit of the use of a .self-filling
excavation The bucket is operated by two
| chains. They are arranged to lead di-
rectly to the friction drums, which arc
/ abreast on one shaft, 10 feet apart center
to center. The engine, of which the drums
are a part, has double cylinders, 10 by l:
inches, and is provided with counter
| shaft and winch heads, by means OF
which the machine is moved upon the
skids as the work progresses"