What is a inexpensive assay for black sand gold?

[bedrock bubba]

I don't want a fire assay.

I want to get grab samples from a large black sand pile. And want a quantitative analysis of gold content of blacks sand, that is inexpensive. If it were up to me, I would roast or grind the BS and put it under a microscope and do a count of visibles. But were talking about huge piles of the stuff, I may want to bid on with the owner if it is rich.

And I don't want to tip them off, and give them the idea to steal from me. So I will present it as a need for organic soil amendment. And what would be a good price per ton as a "soil amendment".
The big assay companies want a fortune to leach test it with expensive leach chemicals.

Any ideas from the inteligencia?

 

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[Clay Diggins]

The only assay that would make sense in that situation would be to process the sample in the same manner as you intend to process the bulk material. Anything else and you are just making up numbers you will never see in the real world.

To put it in broader terms - it doesn't matter how much gold is in the material all that matters is how much you can recover economically.

I'm not sure how they could steal from you when they own the material? I've found that simple honesty can be the best policy in the long run when making a business deal.

Heavy Pans

 

[kcm]

My first question would have to be where did the black sands come from? From dredging? Drywashing? A gravel pit?

2nd question would have to be, what area are you in? If you're not in an area well-known for gold, and if the black sands didn't come from such an area, then they're probably good for rose bushes.

As for trying to figure out quickly and discreetly how much gold is in the black sands, forget it! The ONLY WAY you can do this is to process ALL (or at least a good majority) of the material. Some of the black sands may hold little if any gold, even if other sands in the same pile hold good values.

If there were such a method like you are looking for, it would be in widespread use all over the world!

You can try looking through a loupe here and there and making your best guess, but it will be just that - a guess.

Sorry.

 

[chlsbrns]

Read up on doing an aqua regia assay. It's easy and cheap.

Look up poor mans aqua regia to find out how to make it without having to buy nitric acid. Nitric acid is expansive. Ingredients for poor mans aqua regia can be purchased cheaply at almost any hardware store.

If there is gold in the sands much of it will be extremely small. You won't be able to extract it using conventional equipment. We have gotten over 1,000 grams of gold per ton of black sands. It's easy to extract if you know how!

 

[bedrock bubba]

I think it was from a major dredging operation along a river.

So what is this secret, chlsbrns?

 

[mytimetoshine]

Cant recover using convential methods??.......false.

I'd rather use a rod mill then all those nasty chemicals. What do you do with your waste product

I personally use gravity recovery but a rod mill with mercury amalgamation would be way safer and cost effective.

 

[winners58]

this ^^^^
grind, clean with vinegar, mercury, retort, melt, $profit$

 

[chlsbrns]

Cant recover using convential methods??.......false.

I'd rather use a rod mill then all those nasty chemicals. What do you do with your waste product

I personally use gravity recovery but a rod mill with mercury amalgamation would be way safer and cost effective.

Lol! Rod mills are conventional? Mercury is safe? You really can't use gravity separation on suspended gold that can't be seen by the naked eye.

What nasty chemicals? You don't have a clue what we do!

You can spoon feed your little rod mill if you choose. Our way can process more in a few minutes than you could spoon in a month. Do you use a table spoon?

Back to the topic! Anyone?

 

[DizzyDigger]

Bubba, that black sand could contain much more than just gold.
It's not uncommon for assays to also show the other minerals that
are present. Don't overlook them, as they can be just as valuable
as the gold, if not more in some cases.

If you're talking huge piles of the stuff, then it would be well worth the
investment for the complete assay.

With regards to how you approach the current owner, I would strongly
encourage you not to say what your intended use is. To say it will be used
as an "organic soil amendment", and then processing it for the gold might
get any agreement with the seller nullified, as you made the deal under
fraudulent claims. Don't tell them what you're using it for, just cut a deal to
purchase it in bulk..none of their business what you do with it.

Also, as for the best method, I would encourage you to ignore those who's
posts are written in a manner that makes them feel vastly superior to all others.
They got nuthin' but hot air combined with cut&paste, and if they really wanted
to help you they would just give you the info rather than playing games and
looking for arguments. Directed at no one in particular, just JMHO.

 

[chlsbrns]

Bubba... If a 55 gallon drum held a ton of the black sands how many drum fulls do you think are on the property?

Are a lot of rocks mixed in with the sands?

Are you going to process on site or move the sands?

What State are the sands in?

A small amount of gold per ton of sands, even as little as an ounce per ton would be worth processing. If the sands are from an old dredge operation there is surely much more than an ounce per ton!

We know what we are doing! We have been at it a long time! Let me know how many tons per day that you want to process and I will tell you how in pm's. I can't post the info in the open forum for obvious reasons!

 

[Goldwasher]

I don't think your being dishonest if your just offering to buy black sand from someone. Keep in mind if it is sourced from someone who digs (dredges) in an area and they recover a lot of B.S they most likely have a good idea of what it contains or doesn't they sell stuff "dirt cheap" for a reason...if an aggregate plant is getting gold in their washing efforts they know it and are recovering it. If they are not using a jig on their sand they could be leaving values that are recoverable for profit. If you start asking these questions the seller will know why you want the sands he may help you out a bit...or if he really doesn't know you may "tip " him off but, I doubt you know more about the sand than he does. (not an insult)
Rod mills are helpful if there are particles of gold that can be seen in a microscope you can flatten the particles and help liberate gold from hematite and manganese crusts. The flattened particles are easier to recover with gravity seperation once flattened. I would go with a jig to a shaker table as that is going to be the least expensive way with the most throughput in a system. Spoon feeding anything is not the key to profits with gold the size you may get in those sands.

As Clay mentioned you need to sample in regards to how you plan on recovering. The bigger the sample the better you will represent the bulk material. Chemical based assays are gonna do you no good unless the type of gold is so small thats the only way to tell it is there the recovery methods will get quite involved and gravity seperation will most likely not be efficient for you.
Aren't you in Norcal Bubba? If there are serpentine deposits make sure you do an assay on your magnetic and semi magnetic sands especially the stuff that only a super magnet will get. You may have PGM's if you do your recovery methods will be more complicated.

Mercury is safe when used right and a retort is great. Make sure you learn to use such methods from someone with experience. Someone here with big secrets also uses mercury supposedly, stories change. So, well.........

Royal water is safe if you know what your doing....Who doesn't like to deal with it? Caustic fuming acid!!! Why not make chloroauric acid...you know disolved gold cool ....and you know just keep heating it with hydrochloric acid you have the gold left from precipitation....simple right? And everyone has a place to do it and all the acid and safe places to do this right.....

Aqua Regia will also disolve pgms with the exception of osmium and and iridium. Your refining process will have to change if your running sands with pgm's as the way the royal water effects gold vs. platinum is different. So, using Royal water for an assay may tell you if you have gold or platinum that you can barely tell is there but, it is not going to help you in profitable production of bulk black sands. If you can't step up the process whats the point...wasn't someone complaining about spoon feeding?

The only reason a "MORE" safe and efficient way isn't shown here is that the only methods that exist and are economically feasable are well know and used in the industry on a daily basis coming to a forum and getting a magic method via pm is not gonna happen.

 

[Goldwasher]

forecast....rain with a chance of screenshots!!!!!

 

[chlsbrns]

Bubba, you could do a Purple of Cassius test to see if there is gold. It wont tell you how much per ton. Just if there is gold or not. The darker the purple the more gold there is.

 

[nh.nugget]

AND THESE ARE THE DAY'S OF OUR LIVES!

 

[chlsbrns]

This is decent video showing how easy it is to make and use the test solution. It's just tin and hydrochloric acid. This is just the test solution! You still need to make aqua regia to put the gold,platinum, palladium into solution! It's simple! Real miners have tin, make their own solution and use it regularly!

https://youtu.be/v--lPph0nog

Some more videos: https://www.youtube.com/results?search_query=stannous+chloride+gold+test&nohtml5=False

 

[ConceptualizedNetherlandr]

I don't think your being dishonest if your just offering to buy black sand from someone. Keep in mind if it is sourced from someone who digs (dredges) in an area and they recover a lot of B.S they most likely have a good idea of what it contains or doesn't they sell stuff "dirt cheap" for a reason...if an aggregate plant is getting gold in their washing efforts they know it and are recovering it. If they are not using a jig on their sand they could be leaving values that are recoverable for profit. If you start asking these questions the seller will know why you want the sands he may help you out a bit...or if he really doesn't know you may "tip " him off but, I doubt you know more about the sand than he does. (not an insult)
Rod mills are helpful if there are particles of gold that can be seen in a microscope you can flatten the particles and help liberate gold from hematite and manganese crusts. The flattened particles are easier to recover with gravity seperation once flattened.

Did you mean easier to classify out at a larger size. That is really the deal.

I would go with a jig to a shaker table as that is going to be the least expensive way with the most throughput in a system. Spoon feeding anything is not the key to profits with gold the size you may get in those sands.

As Clay mentioned you need to sample in regards to how you plan on recovering. The bigger the sample the better you will represent the bulk material. Chemical based assays are gonna do you no good unless the type of gold is so small thats the only way to tell it is there the recovery methods will get quite involved and gravity seperation will most likely not be efficient for you.
Aren't you in Norcal Bubba? If there are serpentine deposits make sure you do an assay on your magnetic and semi magnetic sands especially the stuff that only a super magnet will get. You may have PGM's if you do your recovery methods will be more complicated.

Mercury is safe when used right and a retort is great. Make sure you learn to use such methods from someone with experience. Someone here with big secrets also uses mercury supposedly, stories change. So, well.........

Royal water is safe if you know what your doing....Who doesn't like to deal with it? Caustic fuming acid!!! Why not make chloroauric acid...you know disolved gold cool ....and you know just keep heating it with hydrochloric acid you have the gold left from precipitation....simple right? And everyone has a place to do it and all the acid and safe places to do this right.....

Aqua Regia will also disolve pgms with the exception of osmium and and iridium. Your refining process will have to change if your running sands with pgm's as the way the royal water effects gold vs. platinum is different. So, using Royal water for an assay may tell you if you have gold or platinum that you can barely tell is there but, it is not going to help you in profitable production of bulk black sands. If you can't step up the process whats the point...wasn't someone complaining about spoon feeding?

The only reason a "MORE" safe and efficient way isn't shown here is that the only methods that exist and are economically feasable are well know and used in the industry on a daily basis coming to a forum and getting a magic method via pm is not gonna happen.

 

[jeff of pa]

Posts Deleted for obvious reasons.

keep things on Topic & Civil !

You know who I'm speaking to I'm Sure

 

[Ragnor]

My thoughts have always been towards small pvc/halox type leaching systems. There was some arguemwnt against it, but I can't remember it now. It might have been there is a cheaper way or that it doesn't work with 'X'. Been too long.

Crush and amalgum sounds like the cheapest route.
When I imagine a rod mill I see at least 1.5"x36" steel rods. Thats a bit costly to maintain.

If I was gonna process black sands in mass I'd smelt it. Whatever that would take. Assuming of course I had proven the values. Then I would still leach it.
As above, values may not be in just gold. I would spot sample the stockpile and have it assayed or more likely buy the equipment to do it myself.

But These other guys I'm sure have way more knowledge than me. I'm just adding my thoughts to the soup.

 

[Gazaman]

Taking a quantity of black sand and ball mill it down to fine mesh (I like to use #200- to keep the process speedy). Run the ground up black through a high coersivity Neodymium magnet with plastic sorter or a electromagnet to remove the magnetite / hematite and other ferromagnetic materials from the mix.

Next, add some Chapman flux (invented by Hank Chapman and is made up of - Borax, Soda Ash, Manganese Dioxide and Silica) and cook it in a crucible.

You can remove the brick after cooling and look at what you've melted / collected (a pound of black should give you enough to determine the presence of gold, especially if you take the fluxed brick "stuff" and dissolve it in a small quantity of Aqua Regia (Nitric & Sulfuric Acid) and then test with Purple of Cassius (Tin Dioxide) for presence and ballpark concentration.

You can also take the stuff, dice and slice it and "cook" it with a lab spectrometer, gas chronograph or send it out for X-Ray diffraction (its not expensive and assayers use this method to determine your placer gold purity) if you are looking at thorium, silver, copper and palladium group trapped in the sand. Platinum and Rhodium are often worth more than gold, go online and google Pt and Rh spot prices.

Its cheap, quick and its a DIY.

Hope this tidbit helps

 

[Clay Diggins]

Cheap and quick by my reckoning is a $55 fire assay. It's the industry standard for precious metals. Not sure why the original poster would want to rule it out?

If you want the full Monty don't bother with AR/Nitric 2 acid partial dissolution go with 4 acid Total Dissolution Digest for $155.

A good certified assay facility like Copper State will defend their analysis in a court of law as part of their service.

XRD and XRF are very different processes.
X ray diffraction (XRD) is only useful when analyzing solutions or powdered crystal specimens when you are talking ore analysis. XRD tends to be very expensive due to the prep of the solutions.
X ray fluorescence (XRF) is good for analyzing the surface of poured metal bars and getting a handle on soil chemistry as long as you understand the limitations and use a machine with the right profiles and capabilities. Jewelers like to show how "modern" they are by keeping a cheap handheld XRF unit around but not 1 in 100 could tell you the device profile or how to calibrate the machine.

Trying to do this stuff yourself is not only more expensive and dangerous your results are not going to be believed by any serious miner, permitting agency or investor. Stick with a certified assay lab, in the long run they are cheaper and being professionals you can actually rely on the results.

Even with the best assay possible you will never make a full recovery of the valuable portions of the ore. Testing for potential returns needs to be done by the same method as your intended processing system to give you any real world idea of the values you can recover.

As far as Rhodium, Platinum or the PGM group - extraction, benefaction and marketing are several times the cost of free gold processing. Rhodium is below $700 an ounce and Platinum is below $1,000 an ounce. The PGM don't pay nearly as well as gold unless there are a lot more than the gold and you have a market for the raw ore recovered.

Heavy Pans