NEXT MEETING REGULAR MEETING IS Thursday October 7,1999:
Meeting opened at 7:35 PM;
Minutes read and accepted;
Treasurers repot read and accepted;
2 guest were present;
Rock and Gem show at Washington Fairgrounds Oct 1 to the 3rd;
NW mining Expo in Spokane on Nov. 28th, contact Hayden Piper for info;
Bob Schmaltz won the fishing pole raffle;
John Satoris won the 16.8 grain gold nugget drawing;
The 40 grains gold drawing was #937 (Jay Lord) Jay was present to win so it
will be 50 grains in October;
Meeting Closed at 9:20 PM;
Clarence Mohr will give a talk on Power Sluice design a theory at the
October meeting.
SCUBA UNLIMITED is a diving shop at 8450 SE 82nd in Portland. They carry
all underwater equipment for dredgers. If you show them your membership
card they will give you a 10% discount.
Ron Williams is the owner of Scuba Unlimited, and he gave me some advice to
pass along to you.
—If you get a hole in your wet suit do not patch it with aqua seal use a
neopreme cement. A wet suit can not be repaired after aqua seal is used.
His shop will repair suits and diving equipment, including hooka gear. He
also said you should have you hooka gear seviced every year.
HYDRAULIC MINES OPERATING IN OREGON DURING 1932
(Mines without elevators)
Norton & Nelson
Norton and Nelson operated a placer on Galice Creek near Galice during
the 1932 season. The gravel averaged about 12 feet in depth and contained
nearly 20 percent of boulders over 1 foot in diameter and very little clay.
Bedrock consisted of slate of medium hardness; it was rough and had a
grade of one half inch to the foot.
Water was brought through a 1 1/2-mile ditch, 500 feet of flume, and 300
feet of 15-inch pipe. The effective head was 90 feet. The maximum supply was
1,000 miner's inches and the average 600; a minimum of 500 inches was
required to operate the mine. During the 1932 season the gravel was cut
with a no. 2 giant with a 3-inch nozzle and driven by a no. 2 giant with a
4-inch nozzle. Only one giant was used at a time. Most of the water supply
was used as a bywash. The sluice boxes were 20 inches wide, 20 inches deep,
and 10 feet long. Ten boxes were used; the grade was 3/4 inch to the foot.
Hungarian and pole riffles were employed. Boulders were handled with a
2-drum gasoline hoist.
The washing season in 1932 was 150 days; 12,000 cubic yards was washed.
Two men operated the mine, and an average of 80 cubic yards was washed
per day. The labor cost at $4 per shift would be 10 cents per cubic yard;
supplies would amount to about 2 cents per yard, making a total operating
cost of approximately 12 cents.
Salmon Creek
An innovation in placer mining was being tried in July 1932 at the Salmon
Creek mine near Baker by John M. Start. The boulders were removed from
the pit by a gasoline-driven shovel with a 1/2-cubic-yard dipper. The gravel
contained a large proportion of boulders and clay which made it hard to
cut and wash. Insufficient water was available to wash enough gravel per
shift to make the mine pay unless other means of handling the boulders
were provided.
A no. 2 giant with a 2 1/4-inch nozzle under a 150-foot head was used for
cutting the gravel. Wash water coming over the bank assisted the water
from the giant to transport the gravel to and through the sluice. As
boulders were uncovered with the giant they were picked up in the dipper
and cast to one side by the power shovel. When not otherwise occupied, the
shovel was used in loosening the gravel. The power shovel had the
ordinary type of dipper but was to be converted to a dragline with a
clamshell or orange-peel bucket which would work to better advantage.
One foot of gravel, which contained most of the gold, was left on the
bedrock and at the end of a month's run was taken up and washed
separately. The boxes were 26 inches wide and had a grade of 1 1/4 inches
to the foot for 80 feet, then a grade of 1 inch to the foot for 100 feet.
Riffles in the first 20 feet of boxes were iron rails placed lengthwise in
the boxes, The next 60 feet were 4-inch pole riffles also set lengthwise. The
function of the first 80 feet of riffles was to help break up the clay in the
gravel. The lower 100 feet were Hungarian riffles made of 1 1/4- by 1-inch
wooden cross strips iron-clad on top; the spacing was 1 1/2 inches between
riffles.
The operating crew consisted of 1 piper, 1 shovel operator, 2 sluice
tenders on each of two shifts, and a superintendent on day shift. During
each shift one of the sluice tenders was detailed to keep small boulders
moving down and out of the boxes. About 130 cubic yards was washed each
shift. The gasoline consumption on the shovel was 12 1/2 gallons per shift.
With labor at $4 per shift the labor cost per cubic yard would be 12 cents;
at 20 cents per gallon the gasoline cost would be 2 cents per cubic yard;
other supplies and repairs would cost an additional 3 cents and
supervision 3 cents, making a total operating cost of 20 cents per cubic
yard. This does not include rental on the shovel, interest, or amortization
of the plant.
Blue Channel
The Blue Channel mine on Coyote Creek, near Wolf Creek was operated in
1932 by M. C. Davis. The deposit consisted of recent river grovels overlying
an old blue channel. The channel, which contained most of the gold, was in
a depression in the bedrock of the present stream bed; it consisted of
cemented gravel, had a maximum depth of 10 feet, and was about 30 feet
wide.
Water was brought to the mine under a 560-foot head through a 4-mile
ditch and 1,100 feet of 52- to 18-inch pipe. A 4 1/2-inch nozzle was used for
cutting, and 5-inch nozzles were used on the giants for sweeping the gravel
to the sluice. A giant with a 5-inch nozzle was used also for stacking the
tailings. Two giants were used at one time, Figure 11,B, shows the set-up of
giants for working the mine.
The top gravel was first piped off, then the channel was worked by first
blasting a trench lengthwise in the middle of a section of the channel.
After one line of holes was blasted and the broken gravel piped cut, a
second row in the bottom of the trench was drilled and shot. The remaining
gravel of the section was then plowed up with the giant, breaking to the
trench made by blasting. The cemented gravel was disintegrated while
being swept to the sluices. The sluice boxes were 56 inches wide and had a
total length cf 80 feet. A plank fence 12 feet high guided the gravel to the
sluice at the end of the pit. Cross riffles made of 2- by 4-inch timber, clad on
top by 7/16-inch strap iron and spaced 2 1/2 inches apart, were used.
The operating crew consisted of 3 men, 2 in the pit and 1 at the reservoir.
The reservoir held enough water for piping with two giants for 5 hours.
The average piping time for two giants was 5 hours per day during the
season, while at the end of the season only one giant could be used for 2
1/2 hours of piping. The crew worked on boulders while the reservoir was
being refilled. The yardage handled and the days worked were not
available.
(Mines with Ruble Elevators)
Browning
The Macintosh brothers operated the Browning mine near Leland under a lease during the 1932 season. The
gravel deposit was along a small creek and averaged about 12 feet deep.
Preparatory to mining, a 5,000-foot pipeline from the Columbia ditch was
laid. The pipe diameter ranged from 32 to 16 inches. This work took 90 days
with an average crew of l0 men. Further construction consisted of the
erection of a Ruble elevator. Actual washing operations were carried on
for 35 days. Ten days were required when water was available to make a
new set-up of the elevator. Water was brought to the mine under a head of
300 feet. Four hundred feet cf head was available, but the pressure was
reduced 100 feet from the top. The mine was equipped with one no. 4, two no.
3, and three no. 2 giants; 4 1/2-inch nozzles were used on the cutting giant
and the one at the Ruble elevator. A 5-inch nozzle was used for sweeping.
The Ruble giant and one other were used at the same time. The Ruble
elevator was 6 feet wide and 36 feet long and elevated the oversize 14
feet. The grizzly bars, which were set crosswise, consisted of 2- by 4-inch
lumber clad on top with 1/2- by 2 1/2-inch strap iron. The spacing was three
fourths inch. The gravel could be driven over the Ruble as fast as one of
the other giants could get it to the elevator. A timber dam was built part
way across the pit on either side of the Ruble to guide the gravel to the
elevator. The sluice boxes were 4 feet wide and 22 feet long and had a
grade of 7 inches to 12 feet. Standard dredge-type Hungarian riffles 1 1/4
inches wide by 1 inch deep were used.
A total of 30,000 cubic yards was washed during the season. The average
daily yardage was 667. The operating crew consisted of 6 men on two
12-hour shifts; 4 men worked on day shift and 2 on night. At $5 per 12-hour
shift the operating cost per cubic yard would be 4 1/2 cents. The supplies
amounted to another 1 1/2 cents, making a total operating cost of about 6
cents. The labor cost of putting in the pipeline amounted to 12 cents per
cubic yard of gravel moved during the season.
(Mines with Hydraulic Elevators)
Liana de Oro
The Liana de Oro mine was in a flat river valley near Waldo. The deposit
consisted of small-size gravel and clay overlain with soil. Apparently it
contained too much clay for successful dredging. The mine was worked
during the 1932 season by five men under a royalty agreement. The mine was
well equipped and contained a good stock of supplies at the beginning, of
the season. Timber for sluice boxes was cut and sawed, on the premises at a
cost of $8 per M.
Water was brought to the mine in three ditches. The upper had a capacity
of 520 miners inches and was used for bringing water to a hydraulic
elevator. The effective head at the elevator was 360 feet. The middle ditch
had a capacity of 1,800 inches and delivered water to the mine under an
effective head of 125 Feet. This water was used for cutting and sweeping in
the pit and for stacking the coarse tailings. The combined average flow of
the two upper ditches was 700 inches. The lower ditch delivered 10,000
inches which was used in a long tailrace for carrying away the clay and
sand.
No. 3 giants with 3-, 3 3/4-, or 4 1/2-inch nozzles, depending upon the
quantity of water available, were used for cutting and sweeping. A no. 2
giant with a 3-inch nozzle was used for stacking the tailings.
The gravel as cut in the pat was run through 180 feet of 30-inch boxes, set
on a grade cf 5/16 inch to the foot, to the hydraulic elevator. The lift of
the elevator was 44 feet; the diameter cf the standpipe was 20 inches and
that of the nozzle of the high-pressure jet 3 3/4 inches. A second elevator
was used as a water lift. From the elevator the gravel ran through 700
feet of 30-inch boxes, the bottoms of which were lined with sheet steel.
Riffles consisting of steel rails were used in the first 300 feet of the
sluice; no riffles were used in the last 400 feet. The grade of the main
sluice where the elevator discharged into it was 2 inches to the 16-foot
box. As the velocity from the elevator was lost the grade was increased to
3 1/2, 4, and 5 inches to the box. An undercurrent was taken out at the end
of the riffle section. The undercurrent grizzly was 36 by 36 inches in plan.
The grizzly bars had a spacing of 1/4 inch at the top and 3/8 inch at the
bottom. They were set crosswise to the sluice; if set lengthwise, however,
they would not have clogged as easily with trash or grass that came down
the sluice. Black sand had a. tendency to pack in the riffles of the sluice in
the pit and thus reduced their ability to catch the fine gold. To overcome
this difficulty the first two or three boxes were cleaned up daily. Two
thirds of the gold saved was recovered in these boxes. Because of the fine
size of the gold and the relatively large percentage of clay and black
sand in the gravel it was estimated that only 60 percent of the total gold
was saved.
Preparatory work for the 1932 season began November 6, 1931 and
consisted of repairing flume lines and cleaning out the ditches. Washing
started January 1, 1932 and continued to June 20, when the high-pressure
water for the elevator failed. During the washing season piping was done
on an average of 22 days per month. An average of 400 cubic yards per day
was handled after washing began; the daily average for the season was
300 cubic yards, and as much as 500 cubic yards was handled in a day. With
labor at $3.75 per shift the labor cost for the season would be 7 cents;
supplies cost 1 cent per cubic yard, making a total cf 8 cents. The costs do
not include interest, depreciation, amortization, or general overhead
expenses. The labor cost includes 3 1/2 percent for workmen's
compensation.
Plataurica
The Plataurica mine near O'Brien was operated during the 1932 season by
Nelson and Harrison, lessees. The mine was fully equipped when they took
it over. Water was brought through 11 miles of ditch and 4,000 feet of
pipeline 22 to 15 inches in diameter. The branch lines at the mine were 11
inches in diameter. The head was 450 feet.
The gravel was about 35 feet thick. It was fairly easy to wash and
contained few boulders. As no fall was available the washed gravel was
removed from the pit through a hydraulic elevator with a lift cf 54 feet.
The throat diameter of the elevator was 18 inches; a 3 1/2-inch nozzle was
used for the high-pressure water. One giant with a 3-inch nozzle was used
for cutting the gravel and driving it to the foot of the hydraulic elevator.
Usually two or three 16-foot boxes with block riffles were used in the Pit
in front of the elevator. The tailings at the end of the main sluice were
stacked by another giant with a 3-inch nozzle which was operated about 4
hours each day. When the tailings giant was in use the cutting giant was
turned off.
The hydraulic elevator discharged into 256 feet of 30-inch boxes set on a
grade of 6 inches to 16 feet. When the grads were less it was found that
black sand packed tightly in the riffles. The riffles in the upper part of the
sluice consisted of 7-inch wooden blocks and those in the lower end of
4-inch angle irons set across the boxes. An undercurrent was used but did
not recover enough gold to pay for cleaning it. The main sluice was
cleaned up four times during the season. Two flasks of quicksilver were
used during the season.
Work for the 1932 season began November 10, 1931 and continued until
June 25. The operating crew consisted of 1 piper and 1 sluice tender on
each of three shifts and 1 pitman, 1 ditch tender, and 1 foreman on day
shift. The daily labor charge was $40. As much as 600 cubic yards was washed in a day, the
average being about 500.
The repairs on the elevator were excessive. The casting at the bottom,
which cost $157, had to be replaced every 90 days. The lessees considered
the ground too rocky for a hydraulic elevator. The cost for supplies,
mainly in connection with the elevator, was about $1,000 for the season.
The labor cost per cubic yard was about 7 cents, the cost of supplies 1
cent, and the total operating cost 8 cents. If each yard of gravel was
charged with its proportionate share of the cost of ditch and and pipe lines
and of equipping the mine. The total cost per cubic yard probably would be
several times that shown.
(Mines with both Ruble and Hydraulic Elevators)
Lewis
Harry Lewis had been operating a placer mine, working alone, for about
10 years on Rogue River, near Galice. The mine was situated at the edge of
the river, and the fall was not sufficient for a tailrace. The water was
brought to the mine through a pipeline 22 and 15 inches in diameter. The Y's
in the pit were of 13- and 10-inch pipe. The gravel was cut and swept to the
end of the pit by s no. 3 giant with a 3-inch nozzle. There it was driven over a
steel plate with 5-inch holes. The undersize went to a hydraulic elevator
with a 3 1/4-inch nozzle and a 9-foot lift and thence through a 30-inch
sluice box 95 feet long set on a grade of three fourths inch to the foot. The
oversize was swept by a giant with a 4-inch nozzle up a Ruble elevator made
of round poles which raised it 11 feet onto a rock dump. The poles were set
lengthwise and close together. A third giant was used about 1 hour per day
in piping the washed gravel from the end of the sluice boxes. The hydraulic
elevator and one giant were operated continuously during the shift.
The riffles in the sluice were made of sections of 40-pound rails 3 feet
long, placed lengthwise in the boxes. At the end of each section of rails 2-
by 4-inch lumber was placed crosswise in the box. The rails had been used
for 15 seasons and were about worn out.
Three months were, required to set up the equipment and do the necessary
repair work on the pipe lines preparatory to washing. Water was available
for washing for 66 days. An extra man was hired for 6 days while washing.
About 7,000 cubic yards was washed. With wages at $4, the labor cost
would be 8 1/3 cents per cubic yard; supplies amounted to about 1 1/2
cents per cubic yard, making a total operating cost of 10 cents, exclusive
of interest, amortization, or new equipment.
(Mines where water was pumped)
Conners
During the 1931 and 1932 seasons J. C. Conners pumped water for
washing a high gravel bar on Burnt River below Bridgeport. Some of the
gravel which was cemented required drilling and blasting an occasional
auger hole. A few boulders occurred in the gravel. The water was pumped
through 500 feet of 5-inch pipe to a height cf 225 feet. A working pressure
of 65 pounds per square inch was maintained at the nozzle. Two geared
pumps with 4-inch suction and 3 1/2-inch discharge, built for forest-fire
fighting, were used. Each pump supplied 160 gallons of water per minute
under the head used. One pump was driven by a 4-cylinder and the other by a
6-cylinder automobile engine. The engines together used 20 to 25 gallons
of gasoline each shift. A 2 1/2-inch fire hose with nozzles from 5/8 to 3/4
inch in diameter was used for washing the gravel.
The main sluice consisted of a 12-inch box 90 feet long, set on a grade of
three fourths inch to the foot; pole and Hungarian riffles were used. The
Hungarian riffles were 1 1/4 inches wide, 2 inches deep, iron-clad on top,
and spaced 1 1/2 inches apart. At the edge of the pit the gravel from the
sluice box went over a grizzly with 3/4-inch spacing between bars. The
oversize was dumped down the side of the mountain, and the undersize went
through two 12-foot boxes containing riffles consisting of holes bored in a
2-inch plank.
Large boulders were rolled over the side of the hill. Others over 4 inches
in size were either cast over the side or piled on cleaned-up bedrock. About
half the time the hose was used for piping and the other half for washing
the gravel through the sluice. A crew of 3 men operated the mine, 1 man
with the nozzle, 1 working boulders, and 1 on the pumps. The pumpman also
worked in the pit when his attention was not needed at the pumps. About 6
cubic yards was handled per man-shift. At $4 per day the labor cost was
about 67 cents per cubic yard. The gasoline at 20 cents per gallon would
have cost 22 cents per cubic yard; other supplies would have amounted to
about 4 cents, making a total operating cost of 92 cents per cubic yard.
WEB PAGE ADDRESSES:
NWMPC Web Page:
http://www.Geocities.com/Yosemite/Gorge/6503/
NWMP Ore/Wash Gazette Newsletter:
http://www.Geocities.com/Yosemite/Gorge/7278/
OIM Web Page:
http://www.grantgg.com/-oim/
NEWSLETTER SUBMISSIONS:
Submissions to newsletter can be sent to Gary Klier at 8433 SE Lambert Street, Space #139 Portland, Oregon 97266.
E-mail address: glk@grpmack.com (day time) or gklier@juno.com (evenings and weekends)
Deadline for articles is the 15th of the month.
Visit Northwest Mineral Prospectors Newsletter home page
Visit Northwest Mineral Prospectors Club Web page
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