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Post by Jugglerguy on Aug 7, 2014 21:50:40 GMT -5
My son Bryan and I just returned from a three day camping trip to Michigan's U.P. for the sole purpose of rock collecting. We started in Grand Marais and worked East almost to Whitefish Point. Last year when I was in the agate shop in Grand Marais, the owner told me that her favorite agate beach had washed out in a series of storms. She said that the storms had washed the the rocks out and that there was black sand on the beaches which had drawn gold miners. Michigan has pretty strict gold mining rules, so it is pretty difficult to efficiently separate the gold from the sand. You're allowed to collect 1/2 troy ounce of gold per year. I've never panned for gold and my family enjoys watching Todd Hoffman and friends break stuff on Gold Rush, so I decided to buy a gold pan for our trip. I actually bought a small set from the Rock Shed: We found black sand on almost every beach we visited. I only took time out of agate hunting to pan 6-8 pans (I'm slow), but I found gold in every pan. I didn't always keep the gold because it was so tiny it didn't even make sense to take the effort to get out the suction bottle. My goal was just to find gold and I accomplished that. I accidentally left my camera on custom settings for photographing rocks in my basement, so the color is all messed up on these pictures. Before we left for home today, I ran down to a beach and scooped up a half bucket. I don't know if I could lift a full bucket of this stuff, it's really heavy. I didn't take a picture of this particular location, but the black sand was about five inches deep. I picked this up in minutes. The long walk back to the Jeep was not so effortless. So I have questions. I'm going to pan what gold I can from this bucket of sand. Before I left for our trip, I went to a local beach on Lake Huron and picked up some sand that had very thin wisps of black sand on the surface. I was able to pretty easily pan the sand down to a small amount of black sand. I didn't find any gold in it. But when I'm panning pure black sand, I'm not sure if it's as easy to separate the gold. In other words, is the difference in density between regular tan colored sand and black sand larger than the difference in density between black sand and gold? I'm guessing that black sand and gold are of much closer densities. Are there tricks for panning pure black sand? I watched lots of videos on YouTube, but never saw anyone panning large amounts of black sand. I also haven't really figured out the last move in panning where you swirl the last little bit around and separate the black sand and gold with in the pan (without washing anything out of the pan). If anyone has any tips, I'm all ears.
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panamark
fully equipped rock polisher
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Post by panamark on Aug 7, 2014 22:53:45 GMT -5
OMG, I thought at first that there was still snow up in Gran Marias. LOL Good luck on the panning of the black sand. For me it takes a LOT of practice to even get close. Finally I just gave it up and I have 2 buckets of concentrate sitting in the barn for "someday"
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stephent
starting to spend too much on rocks
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Post by stephent on Aug 7, 2014 23:22:18 GMT -5
Any way of just wedging the pan w/sand at the edge of the lake and let the waves slowly "pan" for ya...or at least concentrate it somewhat, while you are doing more important stuff like rock huntin?? lol
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gemfeller
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Post by gemfeller on Aug 8, 2014 0:00:53 GMT -5
The old-time (and frequently current) method of reclaiming the gold from black sand is by using mercury. The gold will amalgamate with the mercury and the magnetite won't. When the mercury's loaded with gold fines it can be retorted. I've seen that done in an old iron frying pan over a campfire. But be sure not to breathe any fumes: they can be fatally toxic. The old-timers would wait for a breezy day, start the retort over a campfire's hot coals, then head off to go hunting or whatever. When they got back the mercury was vaporized away with only gold left in the retort. However, given modern environmental regulations, using mercury may be banned in your area. I haven't looked into it recently.
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unclesoska
freely admits to licking rocks
All those jade boulders tossed in search of gold!
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Post by unclesoska on Aug 8, 2014 0:18:38 GMT -5
Black sand is a mix of alot of different heavy minerals and proportions. There are gold concentration devices on the market that separate the gold from the black sand. The one I use is known as a blue bowl. Does a great job when set up properly. There are many others as you may know. A high concentration of magnetite is often present in black sands. You can sometimes reduce the volume you need to pan by taking a magnet, insert it into a baggy, and then run it gently over the BS in your gold pan. As you start to raise the baggy magnet from the BS, give it a GENTLE shake, and then transfer it to another vessel, remove the magnet and the magnetite will now be separated. This works best with dry BS. You can repeat this a couple of times, stirring your black sands each time. Classification is also a big help in panning black sands, as is panning small amounts at a time. A drop of dish soap will break the surface tension of the water in your pan so that particles don't float. Always pan into a safety pan or tub, and never throw out your tailings, they could contain platinum group metals in addition to the fine gold that's locked up in other material. Hope this info helps!
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Deleted
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Post by Deleted on Aug 8, 2014 10:03:19 GMT -5
I have the blue bowl and it is not perfect but damn close. Amazing how it works. Jim
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Post by Jugglerguy on Aug 8, 2014 10:06:49 GMT -5
Mark, if someday ever gets here and you learn something about black sand separation, let me know!
Stephen - with my luck, I'd come back to find that my gold pan had floated away into the lake. I'm already home, so it's too late to try using the lake action, but maybe next year.
Rick - I remember when I was in high school, our chemistry teacher would put a blob of mercury on the lab table so we could push it around with our fingers. Now, they bring in men in hazmat suits and evacuate the school if someone drops a thermometer. I've heard that mercury is used to separate gold, but I think I'll stay away from it. There's not much if any monetary value to my tiny amount of gold, I was just playing around with it for fun.
Unclesoska - I saw the blue bowl when I was doing a little research before my trip, but this is probably a one time or maybe once a year thing. I'm four hours away from the beaches with the gold, so the cost of the blue bowl doesn't make sense for me. I'll give the magnet thing a try for sure. I ran a magnet under the bowl with black sand from my local beach before leaving on my trip and it was very magnetic. I haven't tried it on this stuff yet.
I was attempting to pan large amounts of this per pan, so your suggestion of doing small amounts is helpful. All the videos I watched started with almost full pans of sand and then panned them down to a small amount of black sand. I guess if you start with just black sand, you need to use just a little.
I did have a problem with the gold and black sands floating. I read that some people use Jet Dry in their pan. Does Jet Dry break surface tension the same as dish soap?
I'm not sure what you mean by "classification".
Is there a way to remove platinum from my sand? You said I should keep my tailings, but for what? I'm not really in a gold mining area, so I don't know who I'd bring them to.
Thanks everyone for your help. If anyone can answer some of my questions above or give me other low to no cost ideas for my playtime with my sand, I'd love to hear them.
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Deleted
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Post by Deleted on Aug 8, 2014 13:17:05 GMT -5
Here is a good link to some chemistry. Dude gives some basic non-mercury chemistry for cleaning the precious metals from the back sands.
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unclesoska
freely admits to licking rocks
All those jade boulders tossed in search of gold!
Member since February 2011
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Post by unclesoska on Aug 8, 2014 19:08:09 GMT -5
Rob- jet dry works really well, but is expensive, though a little goes a long way. A drop or two of dawn works for me. Classification, in practice, separates different grain sizes. If you pan mixed sizes, there's a tendency for the larger pieces to knock some smaller ones out of the pan. Since your material is already sand, you might start by sifting the dry concentrates thru a 30 mesh screen- about the size of window screen, then pan what didn't go thru the screen- you might be surprised! If you have a 50 mesh screen, you could repeat the process. Keep your eyes open for tiny gemstones also, especially garnets. Recovering platinum group metals is a waste of time if there's no known platinum deposits in the area or I should say where the material originated from. When you pan to the bottom and only gold and maybe some whitish grey looking grains , well they could be PGM's. They would move sluggishly in your pan just like gold since it's almost the same SG. And if you find silvery shiny grains that act like gold, well it probably is gold, just coated with native mercury. This is all why you don't pitch your tailings, as there can be hidden treasure OTHER than gold. In quantity they can be sent to a refinery. Cheers!
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gemfeller
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Post by gemfeller on Aug 8, 2014 20:20:18 GMT -5
Rick - I remember when I was in high school, our chemistry teacher would put a blob of mercury on the lab table so we could push it around with our fingers. Now, they bring in men in hazmat suits and evacuate the school if someone drops a thermometer. I've heard that mercury is used to separate gold, but I think I'll stay away from it. There's not much if any monetary value to my tiny amount of gold, I was just playing around with it for fun. Rob, when I was more active with jewelry bench work, a fairly common repair request involved removing mercury from gold jewelry. It was usually the result of accidentally-broken mercury thermometers in hospitals, doctors' offices, etc. The quickest method involves carefully torching the piece (stones usually removed, depending on heat sensitivity) under a ventilation hood to remove fumes. There are other methods but they're more hassle. I'll be checking out one of these days but my demise won't have anything to do with the many times I played with mercury as a kid. Many of the guys carried little bottles of mercury around to play with and use to shine up old silver coins. I wouldn't do that now because I know more and have plenty of respect for potentially dangerous things, but I think our society's gone plumb paranoid over perceived dangers from common materials. Did you hear about the woman who had to pay $2K to have a hazmat team clean up after she broke one of those coiled fluorescent light bulbs that contain a little mercury? Insane.
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Post by Jugglerguy on Aug 8, 2014 20:36:25 GMT -5
Scott, thanks for the link. I read the part about black sand and it was quite informative.
I used a magnet on my black sand this evening and it worked pretty well. There's still a lot of stuff to sift through, but it helped. I put the magnet in a sandwich bag, which worked ok, but I don't think the bag will hold up very long. I thing I'm going to put it inside a plastic cup when I play around more tomorrow.
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Deleted
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Post by Deleted on Aug 8, 2014 21:31:12 GMT -5
If I had large qty of gold bearing black sand like that I would add full strength pool acid for a soak. Easier than a magnet, the iron ores will go away with this treatment, then I'd follow his super clorox or other halogen methods.
You are welcome.
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Post by nowyo on Aug 8, 2014 23:12:44 GMT -5
Just saw this. Was going to suggest the magnet trick but I see that Scott beat me to it. I have a smaller diameter pan that I use for panning cons. If I have more to run, I have a mini-sluice I built years ago. It's set up so it drains into a bucket, has a 12V bilge pup to recirculate the water, and a bypass loop so one can regulate the flow in the sluice. The Jet-Dry works, I use it in the mini-sluice set up, as said above it only takes a few drops. Breaks the surface tension of the water. Looks like you're having fun, had never thought about looking for gold in Michigan.
Russ
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