Kevin you can either buy or make a small recirculating miller table a friend of mine has a black magic I have one made by Jimbo's gold both work pretty good make sure to classify to 50 mesh .

Kevin,

I have some of that flour gold as well. I use a gold concentrating table by Royal Mfg. It works great. With a pan alone you may lose it. 

Scott L.

 

Thanks Brian & Scott
That's worth a try

The fine stuff is the majority of what we get in Colorado rivers, so you have to be good at panning but you also have to have a means of concentrating the micron gold, which is everywhere. Right now the waters are still very high and the flood gold, and I mean flat pickers are washing up on the shores. Right now you can go down to the rivers edge and pull up nice flood gold with just a pan, we were picking it up by hand this last week.

I was caring for my partner that got trench foot and then ended up splitting my knee open on a rock, I got to take a few days off but already planning on heading down again.

DO NOT THROW OUT YOUR BLACK SANDS, you will be sick when you realize that most of it is gold covered in Iron Sulfites.

Benjamin,

I have been saving my black sands. How do you go about removing the iron sulfites to recover the gold ?

Scott L.

First off take a sample to a assayer near buy to determine how much gold is in it, it should cost about $30 dollars. Once you get the information back you have two choices, send it to a refiner, or try to smelt or acid treat it yourself. The easiest and safest way is to send it to a refiner where they can smelt it properly, but this costs more money. Or you can try to do it yourself and use Muriatic acid to let it soak in for days until you have black sands and yellow sands. The yellow sands are micron gold. Then you can choose to smelt yourself (NOT RECOMMENDED) or use Mercury (Also Not Recommended without a retort and a vent hood).

The black sands contain high levels of Tellurium and other impurities and are toxic, you are best off getting it assayed and have a refinery work it for you. Besides working with acid is beyond dangerous if you don't know what you are doing. Just some words of advice from somebody whom has tried everything.

Benjamin,

Thanks for the reply.  Think I will just save the black sands for a while, then send a sample off. Sure don't want to mess with acids.

Scott L.

Benjamin

I was amazed by all the gold - it was all over the place in the river & on the beach!
The gold was on top of the black sand & the black sand was on top of the blond sand - is that the typical flood situation?
There was also some foil type gold & a few bigger pieces but mostly the micro gold you were talking about.

Are you sure that stuff was gold and not mica?

Gee...whats going on out there in Colorado? Sounds like a blast.....gold raining from the skies.

Yeah Leo there is some of that, but there is also gold - one of the local guys had a nice piece in his sluice - "big" pieces we got we got out with tweasers - that's why I was asking about fine recovery.

And it was a blast - you should try it - a lot of work - not raining like you are talking about - but a good time!

Most people complain about Colorado River Gold(All Rivers in Colorado) because it is fine flakes or micron, but it is everywhere. We were picking up flakes with our fingers and it sure as hell isn't Mica. This year is a flood year and the rivers are running 100 higher then normal for this time of year, the flood gold is unbelievable. Now that the water is clearing you can see the black sands and gold lines on the surface, and as I always say, "Follow the Yellow Brick Toad".

We are bringing down a whole Boy Scout troop and giving them pans so they can get their prospecting badges, just a scoop of sand from the beach and you will find many flakes.

That sounds like an awesome time....must be amazing to see it....there must be bigger gold in the deeper waters accumulating

If you have access to a gold spiral wheel, this may be the only instance that a wheel would be useful.

A lot of the gold I find is -100 mesh also, but the gold fever often makes it hard to stop at a point where it's just not worth it. Each piece of gold that small is worth less than a penny. I've heard up to 100,000 pieces per ounce. I'll tell you I've spent an hour getting every last fly poop speck of gold out of the pan, but might not be worth chasing it.

I recommend the wheel because if you classify your cons to greater then 50 mesh, and get rid of that, since there's be no gold, or quickly pan what's left to see if its worth it. The two batches I'd run through the wheel are >100 mesh and the last batch <100 mesh. Using the wheel, I'd say you'd get >95% gold recovery for both batches.

I do like the miller table better, but the difference between the miller table and the wheel is the miller table you load a spoon at a time, and the wheel you load a scoop at a time. If you have a panful of cons, then the miller table would be good, but won't be that great for a five gallon bucket timewise, so the spiral wheel would be better.

I spent a lot of time in the desert with a recirculating system, because the recovery rate is better I estimate 95%, but had I used a dry washer, I would have moved many times more gold through the drywasher than the reciculating system. 80% of tons of dirt moved is much more than 95% recovery of a half ton of dirt.

If you do want to build yourself a milertable, a small pump, a bit of plastic hose, and a piece of slate or metal with chalk paint on the side can do the trick. There's a few videos of home made miller tables on YouTube.

Despite what I said above, I'll bet you someday the five gallon bucket of black sands I have already run through the Wheel, I will put through the miller table when I'm bored, just to see some color. A lot of times finding color is what its all about.

Christopher,

Do you have an recommendations for spiral separators that is designed for gold and black sand mix? 

I was going back through my black sand that I panned and finding as much gold as I got when I panned it.  The miller table is just going too slow for the amount of black sand that I have to process.

Kevin G.

I don't know the details but I've seen mention of centrifugal separators out there.
Seems to me those would be the most efficient.
Anyone know any details about this method?

Cheers!
Mary

Its good that you brought this up. I have had this idea on my mind for quite some time. I really dont know what is available, but the idea of using centrifugal forces to separate solids or liquids with different specific gravity sure is a great way. I can see the gold being concentrated much easily.

I'm curious if a regular medical centrifuge might work. Maybe one of the 10k rpm ultrafuges.
And would the material need to be wet?
Heaven knows the density and specific gravity of gold is far higher than black sands.

I think somewhere in my wanderings I saw one invention, but it might not be hard to rig something else.
Medical equipment (used) is often available on ebay.
Cheers!
Mary

I'm curious if a regular medical centrifuge might work. Maybe one of the 10k rpm ultrafuges.
And would the material need to be wet?
Heaven knows the density and specific gravity of gold is far higher than black sands.

I think somewhere in my wanderings I saw one invention, but it might not be hard to rig something else.
Medical equipment (used) is often available on ebay.
Cheers!
Mary