View Full Version : Which Mining Concentrator works best for Flour Gold ?

30th January 2012, 09:24 AM
I got a demo of a few concentrators (Gold Genie, Blue Bowl) and have been reading up on some of the others (jig, table, cube, centrifuge).

They all seem to have their strengths. I like the Genie (spiral wheel) because the gold concentrate ends up in the middle in a cup - ready to go on to the next stage (refining, melting).

Only one problem - I finally realized that what I have is more like flour gold. What I have is metal that shows up in an assay, but not in the pan. The demo's use gold you can see - small gold flakes.

Some pics -


/\ Gold Genie Spiral Wheel.


/\ Diagram of Duplex Jig


/\ Vibrating tables at the Bjorkdahl facility in Sweden.

I am open to chlorine leaching - once I learn more about it. I'm not in a position to do Cyanide Leaching.

I can afford the Genie, the Blue Bowl, and the Cube. I almost bought the Genie last week - then I realized that what the store showed me & what I had were 2 different things, in terms of particle size.

>>> The Real Question - Do any of the concentrators I can afford do well at processing flour size heavy metal particles ?

Side Notes -

From a theory point of view, if mercury/amalgam is useful in such a situation, sure I'd like to hear about it. But I won't use mercury ... I would like to find the tools that don't rely on mercury.

In terms of quantity of ore, I have a few tons, stored in the ground & in 5 gallon buckets, concrete mixing tubs, etc.

Also, my assays at this point are incomplete ... I should admit. I know I have metal - I also learned, I don't like working with lead to do fire assays.

Someone also suggested chlorine leaching. So I am reading in Hoke about how to work with Chlorine.

I admit that I might be jumping the gun a little. I don't know what metal I have, and yet I'm taking steps to recover more of it. So I'd be using the concentrator as an assay tool - for example accumulating more of TBD metal mixture, a few ounces perhaps, and then using HCl/ HNO3/ AR processing steps to break it into groups.

E. Haney
2nd February 2012, 11:34 AM
O.K. you haven't gotten any responses, I will take this one.
First you say you have tons of material, I take that as you have ore, not placer concentrates.
None of the above methods are going to serve you well, you'll need to leach or amalgamate (which you have ruled out, smart move mercury is just too damned pesky and dangerous).
There are some commercial leaches you could try, one, by a member here. His leach will most likely work, his test kits are guaranteed to work (*snicker, snicker*).
A good all around leach you can try is known as SSN 7:1, seven parts saturated saline solution to one part nitric acid.
You could also use a dilute aqua regia leach.
These are fairly safe, and reducing the gold is fairly easily done.
There are also iodine leaches, (have fun trying to obtain iodine though).
You could also try some 'homemade' leaches, such as hydrochloric acid/bleach or hydrochloric acid/hydrogen peroxide, these are much less 'active' than the above, but readily obtainable and slightly safer.

What you haven't said was your intention, are you doing this for shits and giggles to make a few extra dollars or are you working toward a serious venture.
If you are into seriously extracting the most gold, you would be wise to send off a diverse sample to have assayed to know how much gold is there in the first place, then leaching this same material and sending those tails to be assayed. That will tell you how well your leach is working. Of course this means getting a large sample, homogenizing and splitting it.
If you are doing it just for fun/knowledge/experience any gold you extract is profit, well, after subtracting expenses.

E. Haney
2nd February 2012, 11:59 AM
From a theory point of view, if mercury/amalgam is useful in such a situation, sure I'd like to hear about it. But I won't use mercury ... I would like to find the tools that don't rely on mercury.

Amalgamation works thusly, you grind the living hell out of the ore, mix it with mercury, the mercury amalgamates with the gold/silver/tin, this is squeezed in a chamois to extract as much Hg as possible, the amalgam is placed in a retort (a strong cast iron kettle-like device who's spout is submerged into water [DANGER, DANGER. this spout has to be removed from the water while the retort is still being heated because if the retort cools the gases inside condense and create vacuum and suck the water inside, water and the intense heat of the retort will instantaneously form steam pressures and explode the retort]) the water condenses the Hg fume and the liquid mercury sits at the bottom to be reclaimed and reused. The retort is cooled, opened, and the button (more or less sponge) is refined. You are of course required to report the gold button was retorted amalgam, mercury being that insidious, it's your duty to warn others.

In spite of what others may tell you, or what you read on the internet, mercury will seriously ruin your day, the days of your neighbors and if your local/state/federal authorities learn of your release of mercury into the atmosphere expect a ruined life. Amalgamation is a long dead process because of this.