A Hard-Rock Mining Tale from Mariposa County in the 1980s ......

Rowdy Yates

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This is a story about an experience I had almost 30 years ago during a year of hard-rock mining in Mariposa County back in the 1980's. No actual names are used, but the initials are real, just so if any of you old-timers know who I'm writing about, you will know who I'm talking about. This is the first "chapter". More to follow as I gather my thoughts and try to remember how it really was. Let me know if i should continue.......

Back in the early 1980’s, I was an active gold miner in the Merced River Canyon, located in the Southern Mother Lode portion of Mariposa County, California. I moved to Yosemite in 1980 and after finding my first flakes on Hall's Gulch, I was bitten by the "gold bug” and spent the next 6 years panning, sluicing, busting cracks and moving boulders all over the area. I panned and sluiced every inch of Bear Creek from Midpines down to Briceburg. I also panned and sluiced quite a bit on the South Fork of the Merced (before Wild and Scenic River status), and when the trail was closed for the summer I always had permission to mine out there from L at Savage's Trading Post. I used to do the yearly assessment work for a number of claim owners in the area and once, I spent a few days re-building the mine entrance to the Gold Star mine. It still stands to this day.

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The Entrance to the Gold Star Mine in 2004


I frequently used to visit the LM family who lived in an underground hogan at Hite's Cove on the South Fork of the Merced during that time. RLM was a real nice guy, showed me around the mines, and I was good friends with one of his sons, A. I knew JB at Briceburg well, and needless to say, I became part of a closely-knit group of miners in the area (a few which are included in this story). I even dabbled in some hard-rock mining for a year, which is the subject of this story.


In the spring of 1986, word began spreading around us local miners that an unknown, retired flatlander from Southern California was looking for a “few good men” to help him re-open and work one of the numerous abandoned hard rock mines in the area. Being unemployed at the time, me and ALM from Hite’s Cove stepped up. We offered to meet the retired flatlander at the home of JL, who lived in an older house on the banks of the Merced River near El Portal. JL had grown up here and owned quite a few of the hard rock claims in the area, and was offering to lease one of his claims to this gentleman for a year. Being in my mid-20s at the time, I was impressed with this older, mid-60ish, retired guy from Southern California. Having grown up in So Cal myself, we had quite a bit in common and we hit it off well. He was a general contractor, and his dream was to spend his retirement years getting rich, mining a gold mine. Since he was a general contractor, I knew he was familiar with heavy equipment, and he was bringing in an old miner he knew named J, who had a lifetime of experience mining in Happy Camp, California. At that meeting, I also learned he was going to lease the Rutherford & Cranberry mine. I knew the history of this mine, and when I heard which mine he was planning to re-open, I knew he just might have a chance!

Link to the Rutherford/Cranberry Mine: Rutherford & Cranberry Mines, Clearing House, Clearing House District, East Belt, Mariposa Co., California, USA

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The Rutherford/Cranberry Mine, El Portal, California in 2004


The mine is located on Cranberry Gulch and was discovered in 1863. Ore values averaged 1/2 to 1.0 ounces per ton, with some ore masses containing 100 ounces per ton. In the 1880’s, it was reported that the pyrites assayed upwards of over 1.0 ounce per ton. Workings include underground openings with a length of 579.12 meters and an overall depth of 97.54 meters. The Rutherford Mine has a 320 foot shaft and winze, and a 200 foot shaft with considerable drifting. The Cranberry Mine has 3 adits over 200 feet long, an 80 foot shaft, drifts and stopes.

ALM and I agreed to hire on immediately. Our new boss was named GH, and we decided that we needed an additional worker, so we hired on another local miner, nicknamed “Yosemite” S. So here we were, a 5 man team - GH the boss, J the miner from Happy Camp, ALM from Hite’s Cove, Yosemite S, and, me.

The next few weeks were spent getting preparations ready. The entrance to the mine is at an elevation of approximately 1,300 feet above the floor of the Merced River Canyon, and is only accessible on an extremely narrow and steep 4 wheel-drive road. I had a 1957 Willy’s M38-A1 (first military Jeep with rounded front fenders) and GH had a 1970 Ford Bronco 4x4 with a 302. Our first job was to cut, clear, and make the road to the mine as safe and accessible as possible. After a few days of steady work on clearing the road, we were able to access the mine as quickly as our vehicles would allow.

I’ll never forget the first time I arrived at the mine. The entrance was heavily timbered, and was secured by an iron door similar to the one I had rebuilt at the Gold Star Mine, just a year earlier. There was a 10’ x 20’ skid shed there, which would become our combination office, kitchen, barracks, and general shelter while we were working the mine. We out-fitted it with a few bunks, a desk, and a propane refrigerator, heater and stove. There was a large flat area (about 1/8-acre) in front of the mine entrance, mostly encompassing the top of the substantial tailings pile. The most incredible part, though, was the mining-gauge railroad track extending out of the entrance to the mine, across the flats, to the top of the tailings pile, and a beautifully intact ore cart sitting on the tracks. I swear I saw it sparkle in the sun! At this point, I knew I was to become a bona-fide hard rock miner!

After clearing the road and establishing the mine entrance, it became apparent that we were never going to get GH’s late 1960’s Ford 10-wheeler dump truck up to the mine, so we decided to transport the mill up to the mine, instead of transporting the ore in the 10-wheeler down the steep mountain to our previously established mill site on the river. The mill site was essentially our home base on the Merced River. I don’t know how GH worked it out with the Forest Service (he must have filed a mill-site claim for the spot) but, we took over a fairly large flat on the banks of the Merced River about ¼ mile upstream from the road leading up to the mine. The spot had previously been used as an impromptu campground and had a large campfire pit where we spent many a night slugging down cheap beer and discussing our triumphs and, later on, our downfalls around huge campfires.

Not only was the 10-wheeler parked there indefinitely (we never ended up really using it), but initially all of our equipment resided there at one time or another. GH had acquired a vintage 1945 WWII commercial air-compressor, a gasoline-powered jaw-crusher and a large, trailer-mounted ball mill. Electricity for the mill site and the mine site was provided by two small Honda generators. The ball mill never made it to the mine (too big for the road), but we did get the jaw-crusher up there to pre-process the ore. Also, at the mill site is where J, the old miner, had brought in an 18-wheeler semi-truck trailer converted into his living quarters and a small fire-assay lab, which was permanently moved onto the site. Just like the shed at the mine entrance, it was equipped with propane and had a refrigerator, heater, and stove, along with an assaying furnace. I spent countless hours with J here, learning various assaying techniques, which came in very handy a few years later when I got a job doing fire-assay at Bondar Clegg in Reno, Nevada.

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The Merced RiverCanyon Just Upstream From the Mill Site


And so the story begins. We started out in the Spring of 1986. We had an accessible, excellent past-producing mine, an established mill site, most of the heavy equipment we needed, and, almost a whole year to make it work. And work it we did! All should have turned out well, but we had more than our share of trials and tribulations, which will be the focus of the rest of this story.

More to come.........
 

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Rowdy Yates

Rowdy Yates

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The Story Continues.......... "Chapter Two" - We Open the Mine

The next order of business was to remove some brush and clear out the encroaching vegetation from the staging area outside the mine entrance. Yosemite S was going to spend nights in the shed at the mine to provide “security”. Actually, he was homeless at the time, but he enjoyed carrying his .357 sidearm, and we promptly christened him the “Sheriff of Cranberry”. He had provisioned up with food staples including bread, peanut butter, eggs, bacon, some canned goods, and many, many boxes of Krusteaz pancake mix. We all laughed at this but Yosemite S was a large man, loved his pancakes, and was a very good cook. It was a treat to occasionally arrive at the mine early and have Yosemite S whip up a hearty breakfast of eggs, pancakes, bacon, and more pancakes tossed back with a MGD or two.


A, who had quite a bit of experience, taught by his father out at the Hite’s Mine, was all over the tailings pile with his 10x loupe, searching for specimens and free gold. By the end of the afternoon, he had collected about 20 pounds of samples. We each kept a few as souvenirs, and the rest was taken down the mountain to J, so he could spend some time dialing in his assaying for future samples from the mineshaft itself. Later on, A was to become very intimate with the tailings pile.

Next, it was time to actually enter the mine for an initial inspection. The first order of business was to make a “tag board”, which was nailed to one of the timbers outside the entrance to the mine. A tag board is used to keep track of which miner is underground and who is on the surface. The tag board had two horizontal rows of hooks, one hook directly below the other. We each made our own tags from scraps of sheet metal. We each punched a hole in our individual tag so it could hang on the hooks, and scratched our initials onto it. Each of our tags was hung on the top row of hooks, signifying that we were outside the mine. As you entered the mine, you would place your tag on the lower row of hooks, which meant you were inside the mine. Upon exiting, you put your tag back on the top row.

Hardhats on, flashlights and headlamps ready, we entered the mine. As mentioned, the portal was heavily timbered and we noticed that about 40 feet into the mine, the timbers ended. It turned out not to be an issue, because the walls and ceiling of the mine were solid and not decomposed. We could see where the shaft followed the vein, which was visible on and off on the sidewalls and ceiling. The quartz vein showed abundant sulphides, and ranged from a few inches thick to 2-3 feet thick in places. The surrounding country rock appeared to be mostly schist and slate. The floor of the mine was wet with puddles of water, mostly between the ties of the railroad track, and here and there we noticed that the tracks were obstructed with piles of muck and stones which would have to be cleared before we could use the beloved ore cart. The floor of the main shaft appeared fairly flat and level, but we found out later that there was a slight uphill grade towards the back of the mine. This proved to be useful later as we moved full ore carts out of the mine because gravity was on our side.

A few hundred feet into the mine, we encountered a winze (down shaft), which was almost full to the top with water. This was to become our water source at the mine and proved very useful later on. About another hundred feet, or so, beyond the winze, we discovered an overhand stope (shaft going up) which rose up at an angle on the left side of the main shaft. This was something to be explored at a later date.

We noticed that the mine was wired for electric lighting, as evidenced by a double row of thick, black, cloth-covered wires on the upper right sidewall of the mine shaft. About every 20 feet or so, the wires were attached to the wall with long nails, driven through small, white porcelain insulators into the rock. Porcelain light bulb sockets were wired into the system about every 50 feet or so, but there were no bulbs. We figured it was probably installed back in the 1930s. We didn’t want to mess with it so we went with 6-volt electric battery lanterns instead. As we left the mine that first day, I took off my hardhat about 50 feet before exiting at the portal opening and promptly split my head open on a protruding chunk of rock on the ceiling. I’ve never entered a mine since without a hardhat on.

Later that afternoon, A and I went back into the mine to do some sampling. Not to collect samples from the vein, but to do some test pans from the muddy muck on the floor of the shaft. We pulled a few test pans here and there from the sides of the floor and also from between the railroad ties. We spun the test pans in the water at the flooded winze. I was surprised when we actually found a few nearly microscopic colors. This was a good sign.

The next day was spent mucking out the main shaft, mostly in order to clear the tracks for the ore cart. I also took a hand sledge and busted off the protruding rock I had bashed my head on the day before. Upon first inspection, the ore cart was in very operable condition. It not only dumped to the front, but also dumped to either side. It also had a foot operated friction brake. We greased it up (not the brake) and started up the main shaft, clearing the tracks of muck and rubble along the way. It took about 3 days to clear about 800 feet of track and we ended up hauling out about 6 or 7 full carts of sluff, muck, and debris which we dumped at the end of the tracks, over the side, into the tailings pile. We soon discovered that we could “ride” the ore cart out of the mine from wherever we were working. It took two of us to get it going and empty it at the end of the line, so we would push the full ore cart to get it going, and the chosen “riders” would hop on, one guy on front, and the other on the back to work the foot brake. The brake was pretty much ineffective, but we found that if the “brakeman” put his full weight on it about 100 feet before the end of the tracks, the two of us could slow it down and stop it. I figure the full ore cart weighed upwards of a ton or more. It was quite the experience, rumbling down the tracks, riding a full ore cart with gravity on our side in almost complete darkness, hunkered down so as to not hit your head on the ceiling of the mine. I’ll never forget it.

On the third day, we had almost finished clearing the floor of the mine. We had left an almost full cart at the back of the mine and had gone back outside the mine for lunchtime. A was anxious to finish up, so he ate quickly and went back into the mine to finish filling the ore cart. The rest of us were all pretty much exhausted, so we took an extra long lunch and then relaxed a little while longer in the shade. I don’t remember how long it was, but all of the sudden we all heard a slight rumbling sound coming from the entrance to the mine which got louder and louder. Then we heard an even louder crash and an even louder cussing and screaming coming from near the front of the mine. We all got up and ran over to see what had happened. There was A, he had thrown his hardhat down on the ground, and he was jumping up and down in a giant cloud of dust, shouting the most foulest of expletives I had ever heard (if I repeated them here, I would be banned from the forum). He was bright red, sweaty, and spinning around like a wild dog on the top of the tailings pile at the end of the tracks. And the ore cart was gone.

More to come......
 

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Rowdy Yates

Rowdy Yates

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"Chapter Three" - We Almost Start Mining........

While we were relaxing after a long lunch outside the mine, A had finished filling the ore cart with muck from inside the mine and thought he could “ride” it out by himself, which he did accomplish quite well. Unfortunately, he had failed to remember that it took two of us to stop it at the end of the line. Luckily, he jumped off in time and didn’t follow the ore cart off the end of the track and down the tailings pile. After the dust had settled, we all peered over the side and there was the ore cart, resting on its side about 100 feet below.

It took A three days to get that ore cart back up the tailings pile and onto its tracks. I gotta’ hand it to him. He did it all by himself without help because we all had other work to do, but also because GH, the boss, wouldn’t let us help him because he was a little pissed that the incident happened in the first place. GH did get a good chuckle out of the whole event though. A week later, A had welded new “stops” and installed a new redwood 4x4 across the tracks so no one would ever lose an ore cart down the tailings pile again. The old, original stops had been welded in place near the very end of the track. Of course, they were gone now, having preceding the ore cart down the tailings pile. He installed his new ones about 20 feet from the end. If he ever lost a cart again, it wouldn’t go over the side.

While A was working to get the ore cart back in order, GH, Yosemite S, and I were busy inside the mine collecting samples from the areas of exposed veins. These were taken down to the mill site for J to assay. J was probably in his early 70s, but was as spry as a man in his early 60s. He was short and stout, wore wire-rimmed glasses, and always had a red face. He resembled Santa Claus without the beard. He always wore the same clothes, brown slacks, a white button-down cotton shirt, black suspenders, and, black patent leather shoes. His small propane kiln only held one crucible, but he was able to assay about three samples a day.

Our samples ranged from zero, up to ½ ounce per ton, however one sample, from about 150-feet inside the mine came back at 1 ½ ounces per ton! I remember that sample. It had plenty of visible sulphides, but no visible free gold. GH figured we needed a minimum of ¼ ounce per ton to break even, so he decided that we should begin extracting ore from the vein where the 1 ½ ounce per ton sample was taken. Finally, we were mining!

Unfortunately, we only had 100 feet of air hose for the compressor, and were unable to drill until we got another 100 feet of hose. Since it would be a few days before we could get the extra hose, we first tried single jacking. This is a hand drilling method, where you hold the drill bit in one hand, and using a hand sledge with the other, pound and turn, pound and turn. The vein was about 2-3 feet thick and was on the left side of the shaft, up around eye-level. I gotta’ hand it to the old time miners. This was Hard Work!! After Yosemite S and I had drilled for about an hour, we had only produced two holes an inch or so deep, so we tried double jacking. This is where one man holds and turns the bit, while the other man pounds with the sledge, the advantage being that the man with the sledge could use a bigger sledge with two hands to swing instead of one, and therefore apply more force per strike. We only drilled roughly three inches deep in about an hour, and promptly gave up, aching and sore. It was too much work for so little progress.

Singlejacking.jpg
Single Jacking


While we waited for the extra air hose to arrive, we decided to get the pneumatic drill rig set up so we could begin drilling as soon as the hose arrived. We loaded the 60-pound hammer-drill and jack leg into the ore cart which was back on the tracks, wheeled it into the mine and set it up. We also carted in an electric trash pump and set it up at the water-filled winze to supply water for the drill. Next, it was time to fire up the air-compressor, which was a vintage WWII unit, powered by a flathead 4-cylinder gasoline motor.

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Jack Leg Setup Similar to Ours


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Air-compressor Similar to Ours


This compressor was so old it didn’t have an electric starter, only a hand-crank. We spent about an hour trying to start it, but it wouldn’t fire up, so the job fell onto me to get it running. First I checked for compression and spark by removing a sparkplug and giving the crank a spin. Yes, it had spark and compression, so I suspected a fuel delivery problem. To test this, I replaced the sparkplug, removed the air filter and poured a thimble-full of gasoline into the barrel of the carburetor. I gave the hand-crank a spin, and damned if it didn’t fire once. I remember feeling a split-second of victory as I heard a loud “pop” from the beast as it fired, and then, nothing but an extremely sharp blow to my head and multiple bright lights flashing all around my brain, and then, nothing. I didn’t know what had hit me at the time, but apparently the steel hand-crank handle didn’t disengage, and powered by that one fire of a cylinder had left my hands, spun around once, and caught me square between the eyes on the bridge of my nose.

The blow had knocked me backwards about ten feet and as I passed out, I fell backwards over the side of that damned tailings pile. I don’t know how long I was out, but it could have been quite a while because nobody noticed I was gone, since I was out of sight down the tailings pile. I woke up choking on the blood that had pooled up in my throat, leaking from inside my broken nose. I was lying on my back about 15 feet over the side, with my head downhill from my feet. It must have been quite a sight to see as I crawled up on all fours, over the top of the tailings pile, blood all down the front of me and all over my face and hair. GH noticed me first and hustled me into the shack to get cleaned up and lie down. An hour later, after two beers and a #4 Tylenol and Codeine, I was back to work.
 

Army of 1

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Jun 22, 2013
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Dundee Northern Australia
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Seems the life of a " Hard Rock Miner " is a rather difficult one , but the lure of Gold and wealth keeps the dream alive , looking forward to the next instalment R Y ..cheers Mick
 

Jan 16, 2014
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California - at the other side of the Rainbow
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Hope you continue your story RY, very interesting.... :thumbsup: . I have a few stories myself, but then again, if there isn't much interest shown in the community after starting the story, I can see why you might be hesitant to invest the time it takes to recount your experiences. Either way, I have enjoyed what you've written so far. Thanks

SC
 

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Rowdy Yates

Rowdy Yates

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Nov 15, 2006
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Very well said, Chuck! Yep, after not much interest shown on the forum here, I think I would rather recount my stories around a campfire at night in good company. I'm still committed to continuing the story, I've just been lazy in my old age. I figure it can wait. Stay tuned, I'll get around to writing more, soon. Many more experiences to share......

Regards,

Rick
 

Tampa Steve

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Apr 10, 2014
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Very well said, Chuck! Yep, after not much interest shown on the forum here, I think I would rather recount my stories around a campfire at night in good company. I'm still committed to continuing the story, I've just been lazy in my old age. I figure it can wait. Stay tuned, I'll get around to writing more, soon. Many more experiences to share......

Regards,

Rick
I think this is very interesting cant wait for next chapter..
 

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bs953

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Jan 28, 2015
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RY very interesting. I happened to live in Midpines from the early 70's and knew Alphie, Eddie, Margie and their dad. I also spent many weekends at the hole in the in the ground at Hites cove, since the jersey dale side of the road could be accessed from our driveway on the 140 side. I am still in contact with the family, unfortunately Ron passed many years ago. I will never forget his zeal for the rainbow LOL. I have been in the Goldstar mine many times and as recently as last year. So your the one that put the door on there? I wondered who did that. Since it was literally my back yard there are very few mines I have not been in. As to the Gold Star there is two adz's that are full of water, on my last foray into that mine we managed to get our air tanks in and scuba gear and dove those two, having previously explored everything else we went down 180' and called it off with no end in sight, on the second adze we went down 150' and found a horizontal shaft going east. I collected some ore samples from that shaft which proved out to yield 5 penny weight for one pan. Also I should note that since my last expedition into that mine (prior to last summer) some odd 20 years ago, it has obviously been surveyed as there is string now along the floor.
 

ravensburg

Tenderfoot
Jan 15, 2015
5
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Mariposa
Primary Interest:
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Excellent story so far. It would be great to read more. It seems as if a lot of authors become discouraged because they do not get positive feedback or enough feedback. A lot of people do not post comments because they do not want to clutter up a thread, or they a viewing a thread that may be quite old. It is not because they find the writing uninteresting, because if that were the case, they would not be reading it. I found treasure.net while searching topics on google, and have yet to understand many of its uses and tools. Keep in mind that your stories will be read for many years to come, by people who are not currently active on this website.
 

mariposagold

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May 1, 2012
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Mariposa, California. USA
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A lack of comments could mean people don't want to interrupt the story. I for one, enjoy the prospecting and mining stories, especially in Mariposa. I love to read more about this adventure.
 

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Rowdy Yates

Rowdy Yates

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Nov 15, 2006
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Coulterville, California
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Well, I'm back. Sorry for the delay of the next chapter (jeez, has it been over a year already?). I had some time today, was thinking about continuing with my story, and lo, and behold, here's some more memories. Thanks for waiting.


Chapter Four: "Getting the Ore Out..... We Get Some Drilling Done"

To this day, the bridge of my nose still has a bony bump, a small divot, and a scar as a result of getting smashed by the crank handle. It turned out that the problem with that old air-compressor was a clogged fuel filter. Lucky for us, the filter was the old glass bowl type with a reusable stone filter. I cleaned it out and the compressor was up and running!

The next order of business was to get drilling. The 100 feet of air hose we needed arrived a few days later, and the hammer drill and jack leg was setup at the vein where the ore assayed at 1 ½ ounces per ton. Now we had to tackle the problem of getting water to the drill. Our only water source at the mine was the flooded winze located inside the main tunnel, about halfway between the entrance to the mine and where we wanted to drill. We setup a gasoline Honda generator just outside the entrance of the mine and ran extension cords along the sides of the shaft to the winze in order to power the electric trash pump (no internal combustion engines allowed inside the mine…… fumes and all). Then we ran our waterline from the pump to the drill and we were all set to go.

Air compressor running? Check! Air hoses blown out and running dry? Check! Generator and water pump running? Check! Hammer drill working? Oh my God!!!! What a beast! The noise was deafening. Water, mist, tiny chunks of rock, being blown by the air and water exhaust was everywhere! We were Drilling!! We got about 3-inches deep into our first hole when the jack leg failed and the hammer drill kicked-back out of the hole, nearly taking out Yosemite S who was the operator. A rushed back to the winze and shut off the water pump, and I hurried out to the entrance to shut down the generator and air compressor. Luckily, no one was hurt and the jack leg and drill were OK. What had happened is that the vibration of the drill had loosened the jack leg where it contacted the rock on the ceiling and floor of the mine. We (being greenhorns) had failed to use wood as spacers and vibration dampers at the jack leg contact points. An easy fix, we got some short lengths of 2x4s, reset the jack leg, and were back drilling within an hour.

We drilled well into the afternoon without further incident and managed to finish about three of the dozen or so holes we planned for this first blast. We drilled 1.5 inch holes in the rock, in a specific pattern, to a depth of about two-three feet, and at specific angles. Once the holes were drilled, sticks of dynamite would be slipped into the holes, with different lengths of fuse precisely cut to create a particular blast timing pattern. You might think that a stick or two of dynamite would pulverize the rock and send it flying everywhere, but that's only true in the movies. In fact, the rock usually absorbs most of the shock, and the first dynamite blasts only cracked and shattered the rock in place. Thus, several carefully planned blasts were necessary to blow the ore out into the tunnel and make it retrievable.


attachment.php


Blasting Pattern
Red = Cut Holes
Yellow = Relievers
Green = Lifters



The first blast was always the "cut holes" (red locations, deep and angled in like a pyramid), which made a crater in the center of the rock face. Then the "relievers" (yellow locations, more shallow and angled out) would compress the surrounding rock into the center cut hole. Finally, the "lifters" (green locations, deep and angled out) would launch the entire collection out of the hole onto the tunnel floor, where it would be accessible for removal. The interval between each set of blasts was usually just seconds apart, sometimes even less. But, the blasting comes later. We had holes to drill.

The following day, we continued drilling. For our first blast, we figured we would try and bring down a conservative one ton of ore, which is about a cubic-yard. Our ore consisted of a three-foot thick vein of quartz located on the sidewall of the main tunnel. In most quartz veins in Mariposa County, the heaviest concentrations of mineralization occur along the contact point where the quartz meets the country rock, so we tried to make sure our “reliever” and “lifter” holes included a bit of the country rock, above and below the vein.

The three of us all took turns operating the hammer drill. When not actually drilling, two of us would split the responsibility of monitoring the driller, helping to adjust the jack leg as necessary, and making sure the water pump, generator, and air compressor were running satisfactorily. About halfway through our second day of drilling, we lost our water. We had noticed on the first day of drilling that our water supply in the flooded winze had dropped a few feet, but now the water level had dropped to below the depth of our ten-foot water pump intake hose. This was an easy fix, we just threw another ten feet of intake hose on the pump, and we were good to go.

A few hours later, we lost our water, again! Yep, we had pumped out another ten feet of water and we didn’t have any more rigid intake hose. It was becoming apparent that our water source was not sufficient enough to supply the hammer drill for continuous day-to-day drilling unless, 1) We could get another 10 feet of intake hose and hope that the pump could handle a 30-foot lift, 2) The winze would refill with water by itself naturally overnight, or, 3) We could lower the pump down to the water level into the winze. Being a bit on the lazy side (we were already pretty exhausted that day) we opted for the easy choice of knocking off early, drinking some beers, and waiting until the next morning to see if the winze refilled with water overnight.

The next morning, after an excellent pancake breakfast cooked up by Yosemite S, we entered the mine, only to discover that the water in the winze had risen by only about two feet. This would not do. We had four more holes to drill. We decided to lower the pump down into the winze. I built a plywood deck for the pump, attached it to the top of a truck inner-tube, and we lowered the pump on the inner-tube down into the winze where it floated on the water. I figured that this way, the water level could drop as much as it wanted and the pump would just follow it down. We got another three holes done that day before we lost our water, again! Now what??!?? Well, the water level had dropped to almost 30-feet, and our poor little pump couldn’t handle lifting the water that far, let alone pumping it another 100-feet through the tunnel to the drill. One hole to go. We were almost there!

We had no other choice but to knock off early, drink some more beer, and wait until the next day for the water level to rise so we could finish that last hole. And that’s what we did. The next morning, the water level had risen, we drilled our last hole, and we were finally ready to blast!

But, that’s another story for another day……….
 

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Army of 1

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Jun 22, 2013
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Dundee Northern Australia
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All Treasure Hunting
Thought you might have fallen off the edge of the planet Rowdy , it is a very interesting post , hope we don't have a long wait for the next instalment ..cheers Mick
 

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Rowdy Yates

Rowdy Yates

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Nov 15, 2006
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Coulterville, California
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Thought you might have fallen off the edge of the planet Rowdy , it is a very interesting post , hope we don't have a long wait for the next instalment ..cheers Mick

Cheers back at you, Mick! I haven't fallen off the planet (yet), but I have been busy for the past year getting established up in Mariposa County at a piece of property I bought outside of Greeley Hill. I'm on 5-acres which backs up to Stanislaus Nat'l Forest. I've filed a 20-acre placer claim directly behind the property, and have been running a recirculating sluice when I'm up there on the weekends. Unfortunately, the ravine behind and through my property is dry, so I have to lug buckets of pay material by hand, back to the pump house on my property in order to run it. On the bright side, though, I'm finding that the pay runs about $120 per yard...... I found my first little nuggie a few weeks ago, but it's not the $ that matters...... just consistent gold keeps me happy, and the work keeps me somewhat in shape.

FirstNugget.jpg Gold4.20.15.jpg

Thanks for the interest!
 

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Rowdy Yates

Rowdy Yates

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Nov 15, 2006
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Coulterville, California
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GH (the boss) was an interesting fellow. He was a quiet and reserved fellow, with a cheery disposition and always smiled whenever he was pleased, and even when he was angry. He never raised his voice when he got upset (which wasn’t very often), and he was very easy to like and made friends easily. He was generous and considerate, and treated us “kids” like we were the sons he never had. He trusted us and we trusted him.


But mostly, we were left on our own. He figured we had plenty of mining experience between us, and pretty much only wanted to be consulted when decisions had to be made or equipment was needed. When “Yosemite” S ran out of Krusteaz pancake mix (or I ran out of beer), G had it there the next day. Any gas, parts, or other supplies we needed, all we had to do was ask and it was there. And so, the mine had been cleaned up and mucked out, we had finished drilling for our first blast, and all we needed now was some fuse, blasting caps, and…………. Dynamite!

Sure enough, the next morning, G and his partner J showed up at the mine in his Bronco driving very “slooowwly”. In the back he had a box of blasting caps, two spools of Safety fuse, and, lo and behold, a case of Dynamite. We were all pretty excited about this! He had brought J along because he had more experience with blasting than he did.

Disclaimer: The story I’m telling here is merely my recollection of learning to blast with Dynamite over 30 years ago. It is Not (nor intended to be) any type of instruction on the handling of explosives and/or how to use them! Do not try this at home (or anywhere).

First, we unloaded the blasting caps and spools of Safety fuse which we stored in separate locations inside the skid shed. Next, G carefully unloaded the case of Dynamite which he carried very slowly to the picnic table we had moved to the far side of the flats, away from the skid shed and mine entrance. This was an unopened wooden box of Dynamite which looked kind of old to me. I asked G where he had got it and he said he bought it from BM, an old miner who lived a few miles downstream on the Merced River at Ned’s Gulch. BM was a grizzly, eccentric old guy who lived alone, but a nice guy none-the-less. Anyway, we carefully pried off the top of the box of Dynamite with a small pry bar. We slowly lifted the lid off, pulled aside the wood shavings on the top and got our first glimpse of the explosives inside. Immediately, J said, “Stop, stand back!” The Dynamite was “weepy”.

Dynamite is basically nitro-glycerin (a liquid), infused into diatomaceous earth (a powdery solid), and packed into a heavily waxed cardboard tube. As Dynamite ages, or is improperly stored, the nitro-glycerin will re-liquefy and leak (weep) out of the cardboard tube making it extremely dangerous to handle. J carefully inspected the contents of the crate and determined that only two of the sticks of Dynamite on top had leaked, or had become “weepy”. Sure enough, we looked inside and saw that two of the sticks were covered with small droplets of syrupy liquid. These had to be carefully removed. J put on a pair of gloves, asked for a towel which he laid on the table, gently lifted the two sticks of “weepy” Dynamite out, placed them on the towel and instructed us to remove the box of Dynamite and place it in the shade, some distance away near the entrance to the mine. “Now”, he said, “We’re going to have a little fun!!!”

J took out his pocketknife and slowly scored the outside of the two “weepy” sticks of Dynamite until he was able to carefully break them into four pieces each. Now we had eight “quarter-sticks”. There was a 30-foot long log on the ground, about 50 feet away at the edge of the clearing. He instructed us to place the “quarter-sticks” of Dynamite upright at equal intervals on top of the log. Back at the picnic table, J asked “Yosemite” S (the Sheriff of Cranberry, remember?) for his .357 and promptly shot one of the first quarter-sticks of Dynamite on the log which exploded with a giant “BOOM!” We all took turns, and I must say, it was the most excellent “target practice” I have ever had!!

Now that the dangerous “weepy” Dynamite was safely out of the way, it was time to get down to business and prepare to blast inside the mine. The first order of business was to determine how much Safety fuse was needed to safely accomplish our blast. Safety fuse comes with varying “burn rates”, usually somewhere between 20 to 40 seconds per foot. In other words, one foot of fuse takes between 20 to 40 seconds to burn. As I mentioned, G had purchased two spools of fuse, one of which was rated at 20 seconds per foot (20SPF), and the other at 40 seconds per foot (40SPF).

The main fuse (the one you light) had to be long enough to allow the blasters to light it and safely exit the mine before the blast went off. Additionally, since we were charging three cut-holes and four lifters (we decided it was not necessary to charge the relievers), the end of the main fuse had to be spliced onto seven additional fuses with seven blasting caps inserted into seven “half-sticks” of Dynamite. Here’s how it works:

1) Start at the spot inside the mine where you drilled the holes and want to blast. Slowly walk out to the entrance of the mine and note how much time it takes. In our case, say it takes two minutes (120 seconds). Double that (240 seconds). That is how much main fuse you will need (240 seconds divided by 40SPF fuse = 6-feet of main fuse). IMPORTANT: After lighting the charge, you must always WALK out of the mine. NEVER RUN! Anytime you see on TV or in the movies when anybody runs away from a lit fuse, they don’t know what they are doing!

2) As mentioned, we were charging three cut-holes and four lifters, and we wanted the cut-holes to fire a split-second before the lifters. Using the faster burning fuse (20SPF), we cut and spliced seven additional fuses onto the main fuse. The three fuses for the cut-holes were cut slightly shorter than the four fuses for the lifters so the cut-holes would fire a split-second before the lifters. Then, seven blasting caps were crimped onto the ends of the seven 20SPF fuses. (If this doesn’t make sense, it doesn’t matter because you are never going to try this at home, right?)

3) So now, outside of the mine we have our fuse set up. Six feet of 40SPF main fuse spliced onto seven shorter 20SPF fuses with seven blasting caps crimped on the ends and seven half-sticks of Dynamite. It takes two people to enter the mine, charge the holes and blast. One person carries the fuse and another carries the Dynamite. The blasting caps are never inserted into the Dynamite until you are at the holes to be blasted inside the mine. I was elected to carry the Dynamite, and A was chosen to carry the fuse.

So, hardhats on and flashlights in hand, A and I enter the mine to charge the holes. We arrived at the blasting site, inserted the seven blasting caps into the ends of each half-stick of Dynamite paying close attention to putting the slightly shorter fuses into the Dynamite for the cut-holes, and charged each hole using an iron rod to push each stick deep into the holes. After carefully inspecting that everything was laid out correctly, we lit the main fuse with a Bic lighter. I cannot express in words how hard it was to slowly walk out of the mine (and not RUN!). Three and a half sticks of Dynamite had just been lit! After what seemed like an eternity, we made it safely out of the mine, and two minutes later there was a muffled explosion, the ground shook a little, and we had, hopefully, brought down our first ton of gold rich ore!!!

Of course, we wouldn’t know right away because everybody knows you can’t enter a recently blasted underground mine until the next day……. toxic fumes and all.

More to come……….
 

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