Ronald C reacted to flintgreasewood in Life At The Bottom Of A 64' Shaft
Late December last year I began digging a 6' x 6' prospect shaft about 100' downstream from the original Cobb prospect shaft. Armed with a 30 lb electric jack hammer, a couple of shovels and my nifty 1/2 size home made "Fairbanks self dumping bucket" system I worked my way down through frozen muck and eventually a 10' gravel layer to bed rock at 62'. On my way down I encountered layers of tangled branches and trees up to 6" in diameter. After 40+ feet I hit fine sand and scattered patches of gravel, fossil bone fragments, then complete bones. I was anticipating these finds but the excitement of actually finding them was intense. The first chunk of mammoth tusk nearly put me over the top. Progressing downward, the bones became less frequent and the pay gravel more dense. I had been told that a jack hammer would be ineffective in frozen gravel. Good I don't listen to everything I hear; it busted up almost as easy as the muck. The gravel graded into fractured and decomposed bed rock and I knew I had finally reached my goal...10 months after starting the project. Before freeze up I was able to wash 5 yards of pay and the result was encouraging. I'll have to wait till late spring to resume processing what I brought up before and what I can hoist this winter.
Now it's late November and all is solidly frozen above as well as below ground. Since bottoming out in the shaft I've been devoting most of my time to upgrades above the shaft in preparation for winter work. Also I had to take a part time job in town to help pay for the added expense of moving to a small cabin also in Fairbanks. What little time I've been able to devote to underground efforts have been to expand my working space. On the way down I managed to increase the dimensions of the shaft from 6' x 6' to over 7' square. The plan is to continue out to 10' square before I begin pushing the drifts across the valley.
Jack hammering straight down is relatively easy compared to working horizontally and even vertically. Sufficient pressure is difficult to exert out of position so I began working on ideas to free the gravel other than by the traditional steaming or blasting to reduce the great amount of physical labor involved with jack hammering. Suffice it to say, I'm making good progress in those efforts. I'll report on this process in months to come.
Ronald C reacted to flintgreasewood in 2016 At Cobb
As Jack Nicholson declared in
"The Shining"..."I'm back!!" Finally I have some real progress to
report on. It was early January when I began my new shaft at Cobb
Prospect. Most of my efforts then were done in darkness and below 0
temps but the excitement of a fresh start kept me on task. Now it's
nearly spring with lots of light and often above freezing days.
Actually, nearly the entire winter offered more than bearable and often
downright pleasurable working conditions. Setting up my electric hoist
was not a simple matter; should I have expected different? The hoist
came with a 3/4hp DC motor and controller. The motor was good but the
controller wasn't, so I gave up and switched to a 1hp AC motor I found
on Anchorage Craigslist. It fit the speed reducer fine and it looked
like I was in business but when I put the juice to it the generator
struggled and the motor barely spun. Being somewhat ignorant of many
things electrical I succeeded in letting the smoke out of the motor.
And as everyone knows, motors are run by pre installed smoke at the
factory. When that smoke gets out the motor quits working. Simple! I
brought it in to the local motor repair shop and to my relief I had just
burned out the capacitor. But I also got the news that my generator
was under powered. A friend said he had a 4000watt out at his mine site
that I could borrow so we made the 50 mile trip out [ran out of fuel on
the way] and the next day I hauled it down to the prospect. I should
have paid more attention to the motor technician. A 1 hp motor requires
4400 watts for initial startup. The replacement didn't cut it. I
didn't have the funds to plunk down on a new 5500 watt machine even a
cheap one from Lowes but I applied for and received one of their cards
and was able to get it on credit. The one I picked was marked way down
as it had been bought and returned because it was too small. It was
also a propane only model but I figured I could get along with that. So I
hauled that one down, unpacked it and read the owner's manual. When I
saw how much propane it would consume in a 4 hour run time at 50% power
I was stunned. I'd have to spend at least twice what I would have to
with a gas model. I packed it back up, returned it, picked up a gas
model and hauled it down to Cobb. My plan was to control the hoist with
a cheap reversing drum switch I had used in the old shaft. The wiring
was more complicated with the new motor and it took me hours of analysis
to figure out how to set it up. It didn't work, most likely corroded
contacts. I was fed up and went searching for an industrial grade
switch, found one on an Ohio craigslist and bought it. In the interim I
wanted to use the hoist as I was now deep enough in the shaft that it
was getting too difficult to pitch the frozen chunks of muck out by
shovel. I realized that I could operate the winch by simply making a
setup where I would have an on/off switch and two terminals that would
allow the swapping of the reversing wires fit with alligator clips. It
I wanted to use a standing live spruce for my gin pole and had
available but one that was tall enough I soon realized that the angle
of the carrier high line was too flat between the head frame and the gin
pole. For a temporary solution I erected another gin pole mid point on
the line which provided a steeper slope which would allow the bucket to
generate enough momentum on it's return to trip the release catch.
That didn't help. Next was to increase the hoist speed by doubling the
drive gear pitch. The additional speed and reduced trip time was great
but still wasn't fast enough for the bucket to release. I noticed that
if the bucket dump chain got caught and held the bucket still for even a
couple seconds, enough slack in the hoist line was generated so that
when the chain was loosed, the bucket ran free with enough speed to
release at the trip pin. I rigged up a catch point using a plastic
barrel placed under the trip line. That worked...most of the time, but
not all the time. Adding more weight to the bucket didn't seem to
help. What next to try? I checked the carrier for possible issues and
found an obvious problem . A retracting spring was too stiff and held
the catch mechanism too firmly in place for the trip pin to move it.
Changing the spring helped but still didn't completely solve the issue.
I removed the carrier, took it home removed just one side plate so I
could manually operate the various parts, something I had never done
before. It was easy to see that a bad angle on one of the catch pieces
made it very difficult for it's mating part to slide off to allow the
bucket to release. Those fixes helped even more but I'm still not quite
satisfied; I need the bucket to trip every cycle, not just 90% of the
time. Since I was not happy with my gin pole setup, I decided to erect
an even taller one next to the original and using that one to hoist the
new one in place. Using my chain saw winch I dragged the 28' black
spruce down the hill through 2' of snow, reattaching three times to make
bends in the route through the standing trees. That was, by far the
hardest part of the job. Hoisting the new pole required that I work
from a ladder propped against the old one. A number of guy wires
connected to spruces with ratchet straps and turnbuckles were already in
place including the main carrier line and all had to be loosened, some
removed and repositioned and retightened numerous times. In time I was
able to separate the two poles held together by straps and cut the old
one down, leaving the new, bigger and taller one standing alone. More
wire adjustments brought it straight and true. I had managed to dig the shaft down to 8 feet [that's 8'x8'x8']
and it was time to put in the cribbing. During February I began
harvesting large black spruce, cutting them into 8' lengths, carrying or
dragging them through the deep snow to a sled. I was able to stack 8 or
9 of them to be hauled behind my snow machine down to the shaft site.
As I prepared to start setting the logs I could see there was not going
to be space enough for the bucket to ride up and down the shaft freely
with a cribbed wall. Evidently I would either have to enlarge the shaft
on the one side by at least a foot, or move the gin pole. I almost
couldn't bear the thought of another gin pole change, but the thought of
jack hammering and removing an additional 3+ cubic yards of frozen
muck was even more unpalatable. I knew the gin pole was setting not in a
deep hole but merely just below the moss on frozen muck. If I cleared
out a path through the snow and moss, I could put a comealong on the
pole and simply drag it to the new spot 5' away. I just had to keep
adjusting tension on all the wires supporting the pole. The entire
operation took less than 3 hours and went without a hitch. Amazing! I
now had plenty of room for the bucket to operate.
Cribbing began with placing two over length base logs in place.
To accomplish that I had to jack hammer notches in the walls at the
bottom of the shaft. Sounds easy? It took more than half a day to get
them set and I was whooped. Successive log courses went in relatively
smoothly and I'm now up to just over half way to the surface. At the 4'
point I began placing glass wool insulation between the walls and crib
logs which are set to make a 6' square shaft. So that's where things
stand. Oh, I did receive the new drum switch and found it had a part
missing that kept it from reversing. Just yesterday I made that part in
the machine shop where I am doing temporary contract welding.
Ronald C reacted to plumas.placer.miner in Pandora Mining Company...
Anyone seen this site? Spendy claims, but the web site itself and the photos are great! Love the motion graphics background and the simple interactivity.
It was posted on Reno/Tahoe Craigslist this morning.
Ronald C reacted to chickenminer in 2016 At Cobb
I like the electric jack hammer idea !
I sink holes for prospecting. Never did any serious drifting in any of them.
Over the past 40 winters I've been here in the Fortymile I have probably sank
close to a hundred holes on various creeks in the area.
Here is one I was working on a couple years ago. This one ended up being abt 26' to bedrock.
Ronald C reacted to Sampson Resouces in World May Run Out Of Minable Gold In 20 Years
Interesting topic, it's also interesting following the price of platinum to gold per ounce. Gold has been worth more that platinum only 10% of the time historically. Platinum is an industrial metal, signaling a weak economy when it's price is below gold. Mineable gold? Of course it will run out, not in twenty years. If you research mining companies that trade publically you will find that there is more exploration happening that it seems. South America is a hot spot right now. There is several companies down there exploring new deposits. Nevada also has more than one public company exploring deposits. Ghana has seen a lot of activity as well. Our economy is not on the rise we would like to think it is. The banks are already signaling trouble ahead once again. With the Fed's interest rate as it has been for so long huge companies have been taking out bonds to buy their own stock to make prices rally; as they did all last year. Now the rate increase is coming soon so companies has stopped taking new bonds, and stopped buying their own stock. Hence why the market has suddenly gone sideways these last couple quarters. As soon as this "bubble" takes it's negative down turn, ALL metal prices and commodities will take a huge jump. Then all of the sudden gold will be big news again. So anyways the exploration hasn't stopped, investors are just in an economic cycle that is not favorable to the whole commodities market in general. I honestly think gold will see record highs once again within the 3-5 year range. Minable gold running out in 20 years? That is a foolish idea; there is many new projects underway. We all know it takes 10 years or so to get a hardrock operation into production. By the time our gold has run out here on earth (lets not forget scrap gold) the asteroid miners will have figured out a way.
Ronald C reacted to steve62 in Sampling Methods For New Placer Mine
Carter / Ronald,
Lot's of variables here so I can only speak about what I am doing.
I have a Track-Mounted Hydraulic Auger. Drilling 9 inch Holes down to as much as 20ft. 20ft., right or wrong, is my Cut-Off in terms of how much Frozen Overburden I would be prepared to shift to get at Pay. If I'm not in Pay by 20ft. and the ground is not changing much then I'm out and moving. For example, I have just moved to a new area where a 1907 USGS Bulletin states that Bedrock was reached in a Shaft @ 97ft. The top 40ft. is Gravel but if I haven't hit Pay by 20ft. then I'll move. All the ground is Frozen. If I'm in Pay @ 20ft. I'll keep Drilling.
No need for Casing. Lot's of extra work. Frozen Ground holds up really well apart from the expected Thawing around the collar. Thawed ground is also quite stable. This could vary greatly depending of course on what and where you are Drilling. A Gravel Bar in the River would be problematic for example and apart from the Hole caving, I would expect there would be water ingress at some depth. This tends to wash Sample off the Auger flights.
As far as the accuracy of an Auger, I haven't had any problems and in fact, Sample results can be remarkably accurate and consistent. One way I realised this quite quickly is when I wanted to do some Sample checking so I Drilled a series of Holes on close spacing then Logged the results and found them to be all very similar. I.e. Similar amount of Gold at the same depth sitting on a Clay layer. Barren Gravels still barren. 2ft. Of Clay above Bedrock. Zero colour on Bedrock etc. etc. The talk about Dilution or having additional Sample or even Gold drop off the Flights and fall down the Hole to a deeper layer is not necessarily nonsense but is not a major problem and with your own experience you will soon get to notice anything unusual or out of place in your Samples.
If you are Drilling Gravel you will naturally come across all the various materials such as sand, silt, fine gravel, pebbles, cobbles, greenstone, limestone, quartz, etc. etc. and usually with various amounts of Clay intermixed. We Drill through everything including cobbles up to 8" diameter or larger. I don't know if I have been through much larger than that or not as the larger rock gets ground up in to chunks so maybe I've just been lucky but I do know that the right type of Auger, i.e. Bullet-Tooth which is an aggressive bit configuration, will wear away and break up large Gravel to a certain limit. You will have to sit on it for several minutes grinding away and slowly increase the down-ward pressure until the rock starts to break up but it is do-able and is better than having to abandon a Hole then move and start a new one. These things will get easier with practice. Every Hole presents different challenges. The worst of which for me is Frozen Clay. Sometimes 10 to 12 Ft. of it.
Each Machine will also have it's own limitations and ground conditions will vary widely but it ( Auger Drilling ) can be a very useful way to get a good look at what is below the surface and in my own experience appears to be quite representative although Bulk Sampling of larger volumes will still be required if a Block of Pay can be outlined with the Drilling.
Good luck with it and I for one would be very interested to hear about your experiences.
Ronald C reacted to Geowizard in Ophir Placer Gold Mine - An Example
I arrived early - April 20th.
The mining season usually runs June, July, August.
Late August, things were cooling down to frosty in the morning - that's my signal to wrap it up. A few other placer operations try to work until "freeze-up"
Ronald C reacted to Gambrinus in Canals
Great topic. Around here the ditch companies made a much better profit than the miners ever did, there are over 100 miles of ditches in the Boise Basin District.
Ditches don't always parellel the creek, there was a hydraulic operation in Idaho City, that used water from two creeks.
The old timers didn't start digging ditches just because pumps were expensive, they dug ditches because they did not have portable pumps, like we have today, even a small pump back then was made out of so much iron that you would not want to keep moving it.
Ronald C reacted to Reno Chris in True Cost To Mine Gold - Companies Under Pressure
This is very true and few small miners take these costs into account when figuring their costs. You may have a fuel cost of $200 per ounce, but when you consider maintenance and repairs, lost time for breakdowns, money needed to replace broken equipment, costs to explore for and fine new resources, your real true costs are much much higher than the fuel cost of $200. Ignoring the time cost to do all the other stuff is just denial of the facts.
Ronald C reacted to Reno Chris in True Cost To Mine Gold - Companies Under Pressure
Good point. If you are just doing it just for fun, then you keep on collecting nuts.
If it is a business however, as the price keeps going down eventually its cheaper to buy your nuts at the store then work to find them yourself.
Ronald C reacted to RotGrub in What If
The National stage and our outdoorsmen issues overlap. It is my hope and the opinion of many others that this country is primed to move to the right. Trump is not my first choice nor my last but he has called out the ruling class in a manner that appeals to most Americans. You can argue his policies but the issues are more than valid. For similar reasons we see a socialist giving Hillary a run for her money. Point being everyone is feed up with the ruling class. Don't misunderstand me, I'm fully aware of the difficulty in front of us. Just know that there are people working on this and we are making progress.
Ronald C reacted to flintgreasewood in Tree Burls As Gold Indicators
Some years ago I was told that stands of trees [in that case, spruce] that contained an unusual amount of burls was an indication
of gold beneath the surface, and more specifically, the presence of arsenic that caused the burls to form. Arsenopyrites often
contain significant amounts of gold. Recently I was exploring an area of my claims that have a very strong potential for hard
rock mineralization and came upon a grove of birch and spruce at the top of draw. Nearly every tree, spruce and birch, had at least
one large burl and some had half a dozen or more and many were significantly deformed.
I would like to hear if anyone has any salient information on this subject. So far on line all I could find was one semi
scientific paper making a correlation between arsenopyrite and vegetative dead zones.