Black sand magnet

[2020hindsite]

There are tons of black sand magnets available online from every manufacturer out there.
Are any of them neodymium or are all of them?
Is a regular prefered over neodymium?
I know a regular will pick up magnetite and a rare earth will pick up hematite as well.
I was looking at a Jobe, any good?

 

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[goldenIrishman]

Well with the amount of gold I've been finding in the "coffee grounds" I am going to be changing how I process my sands from now on. Instead of just doing the Shake and Bake, I'm going to grind the snot out of them before cooking them. I don't see any sense in cooking them more than I have to. If they're ground up first that will keep the steps down.

I've also noticed a higher amount of "flour" gold after grinding. It's still a major pain to pan that stuff though so I'll just hold onto them after cleaning the "larger" stuff out and amalgamate them later.

So boredom and thinking outside the box can pay off at times. Whoda thunk?

 

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[KevinInColorado]

Very cool, lots yet to learn, that's for sure

 

[kazcoro]

So, what you are saying is that running the cons through a miller table, then grinding and then shake and baking them, then running through a table, then shake and bake, then table, and you should have gotten it all?

 

[goldenIrishman]

Hummm.... Well I don't use a Miller table yet Kaz. I've been thinking of making one but have yet to find my reserve supply of "Round Tuits". It would be interesting to see how well running the Shake N Bake on a Miller table would work at different stages. If you had a bunch of cons all from the same place I'd think you could do a pretty good test by splitting them into equal amounts. Start with say 4 pounds of cons. Run them all over the table to get what gold you can out of them. Then split it down to four 1 Lb batches.
Do one batch straight Shake N Bake.
Do the second batch by Shake N Baking them two or three times.
Do one batch ground as fine as you can get them, then Shake N Bake them once.
And the last batch ground and Shake N Baked two or three times.

Re-run all the batches on the same Miller Table and see which one gives up the most gold. If I had a Miller Table here I'd do it this week as I've got tons of B.Sands saved up and they all came from the same hole. Ok... Side of the bank but who's going to be that picky?

I think it could be an interesting experiment as well as an enlightening one for all of us. One thing I have noticed is that after grinding as fine as I can, the amount of rust is amazing for stuff that is "non-magnetic". Turns the water in my panning station blood red in an instant!

I would think that after grinding, shake n bake and running them over a Miller Table you would have all of the visible gold out of the materials. After that the only gold left would have to either be amalgamated or leached to get the microscopic stuff. Neither of these processes are for beginners as they require special equipment as well as special knowledge on how to do them in a safe manner.

 

[KevinInColorado]

Sounds like a fun set of experiments to run. Let's do it! (Now I wish we weren't all so far apart )

 

[Kruzman]

And this folks is why mercury was, and still is sometimes used. most gold is too small to see, so it dumped by your armature prospectors, and why professionals use leaching methods. while leaching is beyond most people, mercury is fast and simple method of collecting all the invisible stuff, and while that's not very politically correct, and downright stupid and dangerous under the wrong conditions, it does work. Am I tell you to use mercury? No I'm not. but it is instructional to understand the reasons for WHY mercury is used. studies have found that for every oz of gold retained by a dredge, 4-6 oz went out the back end, and most of that is too small to see. a stream sluice and a pan are more likely to actually retain that gold, which is in the cons. you can get some out through hard work with a pan, you get even less out with a blue bowl but its less work, and a miller table does a darn fine job if you got one. but the only way to get most of it is to dissolve it out, smelt it, or get it to congregate together into larger particle groups that can collected using gravity methods.

 

[goldenIrishman]

Kevin can tell ya that I'm the "Lab Safety Nazi" of the forum here. I'm always "harping" about it. Not that there is anything wrong with using mercury when it's done the RIGHT way, but too many people have caused harm to themselves and others by using it in the wrong way. As long as a person takes the time to do the research into using it in a safe manner I've got no problem with it. It's those that use it in a sloppy manner that I've got major problems with. I just don't do stupid is all.

The grinding doing the Shake N Bake and running the black sands over a Miller Table is just an experiment to see how much gold can be recovered without having to use mercury or other chemical process that many people that are just starting out are not ready to take on in a safe manner. It was in this light that I started this thread in the gold prospecting section. http://www.treasurenet.com/forums/gold-prospecting/392524-processing-how-much-too-much.html

 

[Kruzman]

missed a good method. increase the relative gravity of gold to other material. a centrifuge serves this purpose about as well as can be done with technology today.

 

[KevinInColorado]

missed a good method. increase the relative gravity of gold to other material. a centrifuge serves this purpose about as well as can be done with technology today.

Good point. I'd love to see an affordable desktop centrifuge for the part-time/small-time miner. ' PS: in my post quoted above, the Dredges I was referring to were not the modern portable units like you all use...I was referring to the commercial machines of the 1880-1915 vintage that were used across the US and elsewhere in virgin placers.

PS we need our lab nazi types on here. The info and gear are both available to do it right if you make the effort.

 

[Kruzman]

Low tech: 6ft rope, cone shaped can with threaded cap at bottom and MUST have strong handle, 1 vibrator. tie rope to handle. put vibrator in can, add classified cons to can, add water to can. spin rope around your head slowly letting it out till at full length and do that as fast as you can for about 15min. note: don't you spin around too, loss of balance will probably lead to loss of can... remove cap from bottom of cone, gold will be in the cap.

PS. if asked any questions when buying vibrator say you use it to get Gold.

 

[KevinInColorado]

I like your creativity! Have you tried this and if so, can we see a video?

 

[Goodyguy]

Here's one of the best ways I know to keep from losing any gold due to it getting sucked up to the magnet by getting stuck between magnetic particles.







After that you may want to "crack" the non magnetic black sand to release any gold that is in it.

First Heat the dry non-magnetic sand in the oven at 350 degrees for 5 min. then pour the hot sand into a pan of cool white vinegar with table salt added. That will crack the sand and the vinegar salt solution will remove the oxide films from any gold that was in the black sand.

Note* Acetic acid (white Vinegar) +sodium chloride (table salt)=sodium acetate (liquid) and chlorine (gas). The chlorine gas that is released is minute and should not be harmful but use caution anyway.


GG~

 

[Kruzman]

Please *NEVER* *EVER* cook your cons indoors! Almost all cons have some quantity of mercury in them, or should at least be treated as such. heating mercury converts it to a highly toxic gas, which you and anyone else inside would end up breathing! Will it kill you over night? No, but over time it will mess with your brain, and really mess up your kids. also, depending on what other minerals are in there, you could be releasing arsenic gas as well.

 

[goldenIrishman]

That is an EXCELLENT point nkurban! Mercury VAPOR is more readily absorbed through the lungs than liquid mercury is through the skin. Of course the object is to prevent contact with it in any of its forms. If you're going to do the shake n bake, use a camp stove, do it OUTDOORS and keep everyone else away. Remain upwind from the stove

Many of the old timers used mercury freely and without knowing all of its properties. Much of it was spilled and never cleaned up. Dirty mercury will fragment into many many small pieces that can work its way down to bedrock given enough time. It's not hard to filter it if you have the right tools and safety gear but most weekend miners don't have such things to draw on. Since I'm a lot more than just a weekender as well as a lab rat I've got the proper equipment on hand. I'm even considering installing a full vent hood in the shop for working with some of the nastier stuff.

Recently I was looking into a hard rock claim near the homestead here and when I saw the reports on it I backed away very quickly. Lots of mercury was found in the samples and it came from the late 60s. Even though it wasn't 150 years ago, people were still slopping mercury around like it was nothing. It doesn't have to be in the California Mother Lode area for there to be mercury in the soil.

 

[Kruzman]

And just because the material you have is not from an area where a log of mining took place does not mean there is no mercury. Its tossed around a lot that the mercury is from the miners, but most of it is naturally occurring, and also precipitated vapor from the industrial revolution as well as more recent industry. A lot of mercury went up the old smoke stacks (and still does on old grandfathered power plants and such).

 

[KevinInColorado]

And just because the material you have is not from an area where a log of mining took place does not mean there is no mercury. Its tossed around a lot that the mercury is from the miners, but most of it is naturally occurring, and also precipitated vapor from the industrial revolution as well as more recent industry. A lot of mercury went up the old smoke stacks (and still does on old grandfathered power plants and such).

Hmm, good point. The Chinese are up wind of the whole North Pacific Ocean and North America and they are burning coal like crazy without scrubbers, etc on their smokestacks so there is sure to be some mercury accumulation in our streams. They are the primary reason you really shouldn't eat tuna anymore...too much methylated mercury built up in their tissues because it's in the Pacific Ocean food chain now.

 

[pauldude000]

Here's one of the best ways I know to keep from losing any gold due to it getting sucked up to the magnet by getting stuck between magnetic particles.

After that you may want to "crack" the non magnetic black sand to release any gold that is in it.

First Heat the dry non-magnetic sand in the oven at 350 degrees for 5 min. then pour the hot sand into a pan of cool white vinegar with table salt added. That will crack the sand and the vinegar salt solution will remove the oxide films from any gold that was in the black sand.

Note* Acetic acid (white Vinegar) +sodium chloride (table salt)=sodium acetate (liquid) and chlorine (gas). The chlorine gas that is released is minute and should not be harmful but use caution anyway.


GG~

Goodguy, usually I just read, but I had to post on this one.

>>>Pure chlorine gas is lethal, highly reactive with other elements, and is harmful in any dosage<<<

Use that technique only in a well ventilated area. That needed to be pointed out.

This whole discussion makes me wonder whether black sand forms around gold particles in its formation like snow around dust. Gold has a melting point of 1,948 degrees Fahrenheit, while iron has a melting point of 2851F, so the first to solidify would be the iron, with the liquid gold still inside. The tiny, hot iron particles would rapidly oxidize in the presence of water, forming the Fe2O4 (black rust, or magnatite, verses the red or black Fe2O3 hematite).

A question that the answer could cause room for thought. A simple test would be to buy some coarse black iron oxide, run it through some super fine screen, do the same with some black sand, and compare the weights of two equal volumes of material. If the black sand is heavier by volume with similar particle size, then chemically speaking "something is wrong with the equation".

Anyway, a strong acid should dissolve the magnetite (or hematite for that matter) if I remember my chemistry correctly. After it is dissolved, the whole mixture can then be poured through filter paper to remove all of the gold a person can reasonably expect to recover, including locked up fines. Dry the gold and wash it afterwards to remove any trace acid, and use appropriate safety precautions. Muriatic (HCL) acid that is readily available at a local lumber yard in the plumbing section should work. This will NOT work with iron pyrite, again if my memory serves correctly. I seem to remember a reaction of pyrite to H2O2 (hydrogen peroxide), but don't exactly remember the particulars. Something else to look up.

Hematite and magnetite are both attracted to a magnet, and so is pyrrhotite. Iron pyrite (fool's gold) is not ferromagnetic (attracted to a magnet). What the non-magnetic "black sand" compound that has been described here is exactly, I do not know. I am no Chemist, but pyrite is the only iron compound I know of that is not attracted to a magnet. If there is, someone please let me know.

Something to discuss, at any rate.

 

[pauldude000]

I can't believe that I am probably going to ruin a perfectly good coffee grinder now... thanks alot!

 

[munkirinch]

this thread gave me cancer

 

[KevinInColorado]

The non magnetic black sands can be lots of things such as oxides or sulfides of various metals such as silver, lead, manganese, etc