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Very Fine Gold and Black Sands???? Advice needed


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#1 rluckadoo

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Posted 07 August 2008 - 03:22 PM

I have a claim that is producing some really fine gold. Actually a large part of the gold is so small that you can't really see individual grains, only a rainbow of gold within and around the black sands in a gold pan. But.....there is a LOT of it in there and I think would be worthwhile to get it out. Just wondering if any of you have any suggestions. I am considering getting set up with a Mercury Retort, but just want to make sure there is no other options. This is REALLY fine gold!!! The finest I have ever seen in my 15 years of dredging and mining. So, my desert fox and the other fine gold trapping products that I have won't work.

Thanks for any advice you may have. Also, if you have tips for amalgamation (before I order the stuff to do it with) let me know. Should be a good topic as I am sure many of you have had this problem before, and many others will in the future.

Thanks in advance for your help!

#2 Mike Furness

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Posted 07 August 2008 - 08:05 PM

Rather than take the obvious health hazard chances with mercury vapor ... especially as it sounds you have never worked with mercury before ... have you considered a good vibration gold table? It will separate out some very small flour gold.

Just my twocents.gif !

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#3 jagdoctor1

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Posted 08 August 2008 - 01:37 AM

I personally would love for some one to talk more about shaker/vibration tables!
The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-Herbert Spencer, English Philosopher (1820-1903)

"So go forth, into the placer fields and hunt! Speak to bearded folk and dig a five gallon bucket of rusty crap. Listen to racket through headphones for days, maybe weeks. Bring sunscreen, snake chaps and bug repellent, water and a mild sedative. One day you will find one. It will be very cool." -Bedrock Bob (11/08)

#4 rluckadoo

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Posted 08 August 2008 - 07:38 AM

HI Mike,
Yes, I have thought about a shaker table, but wasn't sure it would get out the really fine flour gold that I am getting here. I have never seen gold this fine, or this much fine gold, back in North Carolina. I have worked with mercury vapors before. Spent 4 years working as a geochemist (I am a geologist) in a lab at NC State University where we used a Mercury Vapor Extraction line; however, I have not used it in an amalgamation process before. I do know the health risks though.

I would definitely be interested in hearing other ideas of how to get this really fine gold out of my concentrates. To give you an idea of the quantity of the fine gold that is in there, when you pan down a clean up to the last 2 cups or so of black sands (after screening to window screen size classification), there is almost as much fine gold as there is black sand left in the pan. It will definitely be worth my while to get it out in some fashion.

ANY SUGGESTIONS WILL BE GREATLY APPRECIATED!!!!! Thanks in advance.......


#5 sawmill

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Posted 08 August 2008 - 10:49 PM


From your description of the concentrates,a micron wave table
would recover more of the fine gold ,cheaper ,and faster than
mercury. Our Friend Mike is right on track with his suggestion. innocent0002.gif
The wave table is a vibrating table,and designed to do just
what you need. They will recover free milling gold that you need a
microscope to see. They will concentrate clean enough to direct
smelt too. woohoo.gif

#6 Mtnman

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Posted 09 August 2008 - 02:34 AM

From your description, that is some small gold. Any idea on an approx. size? Gold of less than 600 mesh won't amalgamate, so that would be a waste. Try the Blue Bowl, sounds like what you may need. For the best recovery, run the different classifications by themselves i.e. <30, <50, <100, <200, and so on. Good Luck.

Randy

#7 jagdoctor1

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Posted 09 August 2008 - 02:11 PM

ON the last post of the forum page I am going to copy here there is a fellow talking about using a table and mentions sizes and such he seems experienced. You may want to read the thread and contact him.

http://www.arizonago...i...31&start=31
The ultimate result of shielding men from the effects of folly is to fill the world with fools.
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"So go forth, into the placer fields and hunt! Speak to bearded folk and dig a five gallon bucket of rusty crap. Listen to racket through headphones for days, maybe weeks. Bring sunscreen, snake chaps and bug repellent, water and a mild sedative. One day you will find one. It will be very cool." -Bedrock Bob (11/08)

#8 rluckadoo

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Posted 09 August 2008 - 02:32 PM

Thanks for all the suggestions! I would definitely rather use a table than the Mercury! I definitely know the risks and having a great deal of prior geochemical lab experience, I also know the "pain" to do amalgamation safely and effectively. So, it is kind of a last resort. But, there is a LOT of fine gold in there, so I need to get it out. I just went and purchased a 50 mesh and a 100 mesh screen at Smokefoot in Morganton, today to see what size it really is. I didn't have either of the two before, because we just don't find this really fine stuff in NC that often (or either I just have never noticed that much of it). So, hopefully in a day or two, I will be able to report the approximate size.

Does anyone know a brand name, or a website for the Micron Wave Shaker Table. I was getting ready to order some amalgamation supplies, but will definitely check into the table if it seems it will work. Also, thanks Jagdoctor for the thread on the hard rock prospector with the fine gold. I have joined that forum today, to be able to contact him via the forum. I will let you know what I find out.

Let me know if you have a name or a website for the micron table. I will check it out ASAP.

Thanks again,
Robert

#9 jagdoctor1

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Posted 09 August 2008 - 06:32 PM

Huh_anim].gif Wow this thing sounds BADASS! I don't know what your budget is but I can tell you I surely want one of these!
I just did a yahoo search on micron shaker table. It even floats your black sands man!!!
http://globalminings....com/index/rp-4

P.S. You said you were going to order the amalgamation chemicals and equipment I can't imagine that the table is more expensive than the startup of the other. I don't know though ...
The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-Herbert Spencer, English Philosopher (1820-1903)

"So go forth, into the placer fields and hunt! Speak to bearded folk and dig a five gallon bucket of rusty crap. Listen to racket through headphones for days, maybe weeks. Bring sunscreen, snake chaps and bug repellent, water and a mild sedative. One day you will find one. It will be very cool." -Bedrock Bob (11/08)

#10 rluckadoo

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Posted 09 August 2008 - 07:55 PM

Found another site for a Micron Vibrating Separator Table: http://www.actionmin...com/tables.html

Also seems to be an Awesome table, but very expensive, even for the "sampling" model. (around $4000). This is the table that the hardrock prospector from the other forum has set up in his garage to run his crushed material through. Says he really likes it, but still leaves about 30% of his gold in the concentrate line. About 70% of the gold (especially the larger particles) are recoverable as clean from the table. Would still leave some gold to clean up by amalgamation or some other process.

I have priced out getting set up for a very small scale amalgamation process including retort, small tumbler, and accessories, including chemicals.......(about $500-750 depending on the size of the tumbler and how much mercury you purchase)

#11 jagdoctor1

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Posted 09 August 2008 - 10:57 PM

What about time and hassle? I don't know about mercury personally but I bet it will take along time to asertain. Agua regina takes constant PH monitoring and from what I can tell all of the chemical processes are alot of attention/work.I personally have children and could never consider doing that sort of process however if it is best for you so be it. Whatever works out I am glad you found a good site and good luck. I have a lode site and am looking for a better way to run my crushed ore faster than the small sluice without further expense since I just bought a detector.
The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-Herbert Spencer, English Philosopher (1820-1903)

"So go forth, into the placer fields and hunt! Speak to bearded folk and dig a five gallon bucket of rusty crap. Listen to racket through headphones for days, maybe weeks. Bring sunscreen, snake chaps and bug repellent, water and a mild sedative. One day you will find one. It will be very cool." -Bedrock Bob (11/08)

#12 sawmill

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Posted 09 August 2008 - 11:57 PM


rluckadoo
I suspect that the table Paul has ,is a M4.
If it is,they are for lab use ,and not a production table.Also the M4
was discontinued and replaced with the M5. The M5 is bigger and
does a better job. The M5 has only been on the market for a couple
months.
The M7 is capable of recovering 600 micron gold,and it will produce
gold ready to smelt,with a high recovery rate.
The key to the whole system ,is knowing how to use it. The black
sand tails need to be reclassified and rerun . Classification is the
secret to recovering all the fines in any process.
The downside is the M7 costs around $5,800.00,and is designed to
run a ton per hour,and is not real portable.
I have a friend that uses two M7's for the final finish ,before shipping
to the smelter.
I feel that the M5 would recover everything ,if a guy took a little time
to learn the machine,and made the effort to classify his reruns.
Of course the bad part ,is finding enough pay dirt, to justify the initial
cost. laught16.gif


#13 El Dorado

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Posted 11 August 2008 - 08:04 AM

Why not use an old method that is still in use today...... flotation. Method was discovered during gold rush when women would wash miners clothes and they noticed fine flour gold floating on the soap bubbles
El Dorado

#14 visitorbedrock bob_*

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Posted 12 August 2008 - 09:40 AM

Here is my two cents worth... If it does not clink, clunk, or clank when it hits the pan move on. If you still want to trap the fine gold just make concentrate and sell to a refiner. Black sand concentrate is not nearly as tough to refine a most ores, so it is salable to someone with a small refining setup.

Two very good methods are SSN (saturated saline and nitric), as well as cyanide. Both methods are easy, cheap and safe if you do them right. If you are not familiar with basic chemistry then dont go there. Beter left to those with the knowledge and equipment.

Any simple electrowinning process can strip all gold and silver out of solution, and there are many who have small processes for film developer and dental waste out there, as well as those who recycle catalytic converters for Pt. The trick is your solution and how to reduce it to something you can pour out the back door. Thiourea is good too, but this is not a hobby. You will spend much less time and effort finding someone interested in purchasing the concentrates than you will trying to fiure out which process to use.

In any case you would not even try to separate the gold from the fine black sands. A magnet with a 1/8" spacer ran over a fine bed of (pulverized) concentrates while underwater is as close as you can get. From here on out it is as simple as firing the concentrates in a small oven. This is how the old timers handled it, but the time and effort involved means you will need a pile of concentrates to make it pay and a steep learning curve if you have never watched a crucible of molten slag boil over in the oven.

When you get gold like this it is very common to have 3-8 times more silver in the cons than gold, and the silver is MUCH easier to get loose by chemical means (usually). For a couple of five gallon buckets of fine concentrate I would simply split the dry samples very well, fire assay so you know what is in there , and sell the stuff based on what is in there.

Bobby

#15 Randy Wright

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Posted 13 August 2008 - 08:46 AM

QUOTE (jagdoctor1 @ Aug 9 2008, 06:32 PM) <{POST_SNAPBACK}>
Huh_anim].gif Wow this thing sounds BADASS! I don't know what your budget is but I can tell you I surely want one of these!
I just did a yahoo search on micron shaker table. It even floats your black sands man!!!
http://globalminings....com/index/rp-4



A friend of mine created those :) If you have any questions let me know. I'll ask him personally. Yes, they're badass. He says they recover down to 1 micron.
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#16 Mtnman

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Posted 14 August 2008 - 06:11 AM

Bedrock, nothing personal, but I'd shy away from making that type of post to someone who is new. Any time you start talking about the leaching process, please include the dangers and regs regarding something like that.

#17 visitorbedrock bob_*

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Posted 14 August 2008 - 08:19 AM

Point well taken. Here is what I wrote...

Two very good methods are SSN (saturated saline and nitric), as well as cyanide. Both methods are easy, cheap and safe if you do them right. If you are not familiar with basic chemistry then dont go there. Beter left to those with the knowledge and equipment.

I stand by that. If you do not have the knowlede and equipment then find someone who does.

The method by which fine gold is recovered from waste material is cyanide. I am not sure how to respond to a question like this without mentioning it. There are dangers and regs applicable to everything that need to be considered. Driving, digging, heap leaching and sex all fall into this category.

As far as regulations I know of very few that would preclude the use of this process unless it was done on a commercial scale. Even still it could definitely be at least as hazardous as driving while drunk, digging in unstable gravel, or sex without a condom. So be advised.

If you want the skinny on the process here is a good article...

http://www.prospecto...ml/cyanide.html

There are many dozens of labs all over the west that employ this (and the other mentioned) processes. Many will buy the concentrates at a "fair" price. I have handled tons of concentrate such as this and sold most to the Phelps Dodge Refinery in El Paso. The fellows there were great and paid me well based on the assayed value of the material. After dealing with several small refiners I found no reason to go anywhere else but PD with my by-products.

So, I am not advocating anyone go out and start a backyard leach process. Just answering a question on what to do with fine gold concentrates. There are a lot of gravity concentrators out there that will get you close to the gold, but none that I know of that will produce a refined product. Chemical extraction, electrowinning or fire is the only way to make the fine stuff into gold. Period. If anyone out there knows a better way please let the industry know! A prospector should probably stick to his job which is finding and concentrating gold and let the refiners do what the refiners do best. In my experience I wasted a lot of time worrying about the fine stuff I was missing rather than concentrating on the coarse gold I was getting. In the end I just took what went clink, clank, and clunk, and sold the pulp for a nice profit to a refiner and skipped the worry. Anything that does not crawl out of the black sands by itself when you tap the pan is destined to be plating on a cheap pair of sunglasses anyhoo.

Bedrock Bob

#18 sawmill

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Posted 14 August 2008 - 01:17 PM


Bed Rock Bob is right about refining for pure gold,also the methods
can be found on hundreds of internet sites. There is at least two forums
that I know of dedicated to precious metal refining.
But this thread was about separating or concentrating fine gold from
black sand,not recovering pure gold.

I made a typo on the wave tables,it should read 600 mesh,not 600 micron.
The tables are just finish concentrators,and as I stated above if used right
they will produce gold clean enough to direct smelt.

Also the table Randy Wright mentioned is limited to small mesh concentrates,
clean water supply,and it has to be mounted to bedrock or concrete to work
right. But this table would do the finish work just fine for a small operation.

The small sample and lab tables would be great,if you produced enough fines
to justify the cost. Chasing fine gold can be an expensive process to produce
enough to make it pay. I wouldn't waste time trying to leach or refine on a small
operation. Concentrate it down as clean as you can get it and ship it out to a
refiner.

Also if you are producing enough ore or sand from a casual use claim to
justify high volume finish equipment,you may want to think about a plan of
operations. laught16.gif

A dredger would probably produce enough ,but us dirt scratchers might have
a tough time telling Ranger Smith those 20 foot high tailings piles,was caused
by gophers. ROFL.gif


#19 wyldkatt7

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Posted 14 August 2008 - 04:52 PM

QUOTE (sawmill @ Aug 14 2008, 01:17 PM) <{POST_SNAPBACK}>
,but us dirt scratchers might have
a tough time telling Ranger Smith those 20 foot high tailings piles,was caused
by gophers. ROFL.gif



Ya think????????????????? rofl2.gif rofl2.gif rofl2.gif

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the farther forward you will see..."
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#20 rluckadoo

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Posted 21 August 2008 - 06:48 PM

QUOTE (Mtnman @ Aug 9 2008, 05:34 AM) <{POST_SNAPBACK}>
From your description, that is some small gold. Any idea on an approx. size? Gold of less than 600 mesh won't amalgamate, so that would be a waste. Try the Blue Bowl, sounds like what you may need. For the best recovery, run the different classifications by themselves i.e. <30, <50, <100, <200, and so on. Good Luck.

Randy


Randy,
You mentioned the blue bowl. Just wondering if you have worked some really fine concentrates with the blue bowl before? Pioneermining.com has a pretty neat video of the blue bowl in action, but the gold they are using seems to be pretty large pieces. Would be interested in hearing from others who have used the blue bowl on very fine concentrates. Thanks, Robert




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