Electrostatic Fine Gold Recovery.

Any body tried  to do this ? Would you like to tell and show ?   Many years ago...   I met a guy at Oallen Ford , he had a sluice  box running , on part of the sluice  he had some plastic sheeting from a mushroom  farm. Well that's what he told me ...   Not sure if it was magic  mushrooms or not ...    He said that the very fine gold stuck  to the plastic , because of the electrostatic attraction ,  he had to scrape it off.  Like most gold prospectors  ,  he did not want to tell me too much .

G'day Mike

Maybe it's possible, I don't know much at all sluices, but the Keene dryblower claims this, "Some of the new features include “Soft Bed Technology” that creates greater electrostatic charged recovery bed" http://www.keeneeng.com/mm5/merchant.mvc?Screen=PROD&Product_Code=151S

cheers dave

I guess the idea is not new.
http://www.mine-engineer.com/mining/edison.htm

I guess the trick is to keep everything dry??

minermike that old guy sounds like Martin Marks he used to claim something along those lines.
Rowdy

Keene Engineering Model 151 Dry-Washer/Dry-Blower - which uses hot air to capture micron and sub-micron gold... along with nuggets and coarse alluvial gold.

STATIC CHARGE for GOLD RECOVERY using a Dry Washer with Hot Air...
A modern Dry-Blower use electrostatic charge to capture fine (usually micron and submicron) gold.  I owned a recent Keene Engineering Model 151 Dry-Washer/Dry-Blower and it had the improved Honda motor (blowing warmer air than previous models) with a collection port for emptying the fine gold that was trapped. You can see the tiny collection port hole on the lower left hand side of the bottom section in the image above.  Normally a rubber-sealed metal hinged plug goes into the hole to seal it.  A newer version uses a Briggs-&-Stratton motor which was cheaper for the manufacturer to supply.  The hot air is a necessary part of the capture process ...and the hotter air increased static and therefore gold-capture. But I didn't get a chance to use it (it was sitting in my lounge-room for a year or more) and so, with considerable encouragement from my wife, I chose to sell it a couple of years ago. It was a member of this forum who bought it from me.  (Perhaps he could offer some input from his own experiences if he reads this post?)

Gold can take on a temporary electromagnetic field as a metal detector coil passes over it... although gold itself has no detectable magnetic qualities. For a dry-blower, the finer gold will take on a static charge and will stick to parts around the riffle tray as the coarser ore passes over the tray, enhancing the static charge on the synthetic mesh beneath the riffles ....and hopefully this increases the capture of more gold.  


Closeup of the Riffle Tray of the Dry Blower - which has a synthetic mesh below it.  The entire tray is removable for cleaning.

IMAGE ABOVE: The hot air pushes up beneath the synthetic mat and blows away dirt, allowing the gold to remain on the mat.... partially from fast-movment of the soil over the riffles and partially from the static charge from the hot air and the friction on the synthetic mat.  The riffles on the Dry-Washer (which point UPWARDS on a dry-washer, unlike on a sluice) capture any nuggets or coarse gold.  The dirt flows over the top of the riffles and increases the static charge on the mat. The fine gold passes THROUGH the mesh and ends up being collected insider the lower hopper.

If you ever open one of those resealable plastic bags with a few grams of fine alluvial gold inside, you'll see that the gold often sticks to the inside walls of the plastic bag as soon as you open it.  It's the same principal that allows a Dry-Washer/Dry-Blower to capture gold.

Static Charge + Water = Nothing
Water will dissipate any static charge though.  So anyone operating a water sluice and claiming that he's using 'electrostatic charge to capture gold' is either confused by what he's actually supposed to be doing or he's trying to throw you off what he's actually doing with a bit of misdirection.  The area around Oallen Ford (NSW) is known for extremely fine gold... literally as fine as mustard powder. So it would actually be a great place to use a Dry-Blower or similar technology for recovering the fine gold there.

I might add that there's a well know sluice maker who believed that metal sluices "repel gold" in water and that plastic sluices and gold pans "attract gold".  I've disagreed with him a couple of times over this because there's no scientific basis for his claims ... yet he's quite passionate about his belief.  But perhaps he knows something the rest of us don't?  Since he operates on Oallen Ford, and since he sells sluices designed to capture the fine gold in that district, it's entirely possible the sluice operator you met was given the same explanation from the sluice-maker.  I remain skeptical of this ability involving water instead of dry air. (I see Rowdy knows the chap and is familiar with his argument). The last time the Sluice-maker and I met, I think we argued over this very subject for almost 45 minutes without either of us backing down.  I note though that he is the only person I know who shares this belief.

Please explain:
Are you saying the fine/mustard gold passes through the riffle screen and collected in box underneath?????? Along with an even greater collection of electro magnetic dust - Iron stone and the like.

Hot air delivery, that's all it is! Helps dry the soil.
We once tested a Keene hot air delivery dry blower up against a standard bellows type dry blower.
We ran the fines discharged from the bellows type back through the Keene, result = zero -AU
We ran the fines discharged from the Keene type back through the bellows, result = multiple specks of very fine AU.

Welcome anyone to put this to the test and prove me wrong.

Nightjar wrote:Please explain:
Are you saying the fine/mustard gold passes through the riffle screen and collected in box underneath?????? Along with an even greater collection of electro magnetic dust - Iron stone and the like.v

Yes. That's how the Keene models are designed to operate.  The accumulation and capture of the fine micron and sub-micron gold is a bonus byproduct of the static charge caused by the soil racing down the lower portion of the unit and over the riffle plate.  The static charge is a combination of friction and hot air. The hot air is meant to blow off a lot of the lighter debris (soil) as it passes over the screen.  Yes, the hot air will dry the soil slightly but your soil is supposed to be dry BEFORE you run it through the dry washer... which is why people often lay out massive tarps on the ground and shovel their ore onto the tarp to allow it to dry out before feeding it through the dry washer.  Feeding damp soil through a dry washer is less than ideal.  I should have mentioned before that the Keene 151 dry-washer is a VIBROSTATIC machine.

[FROM THE KEENE MANUAL]"The Keene 151 drywasher uses three processes at the same time to recover gold. Electrostatic concentration occurs because the high-velocity air flowing through the unit creates an electrical charge which attracts and holds gold to the riffle tray cloth like a magnet. The same airflow then holds the material in suspension allowing the heavier materials to sink into the riffles where it is caught. The adjustable oscillating vibrator shakes the material at the same time further helping the gold to sink.

The Keene hot air induction blower helps create static electricity and allows you to run material that is damp. High velocity air passes through the concentrator creating an electrostatic charge to attract gold and other metalliferous values. The hot air from the engine is ducted into the radial blower, preheating the air and concentrator to 50 degrees above ambient making it possible to process a higher capacity of material and increases the electrostatic charge."

Nightjar wrote:Hot air delivery, that's all it is! Helps dry the soil.
We once tested a Keene hot air delivery dry blower up against a standard bellows type dry blower.

The earlier models offered warm air from the motors but the hot-air models came later. Keene have had around 8 varieties of Dry Washer, including several old-timer bellows systems (which are NOT suitable for submicron gold retention) which do not offer electrostatic (aka Vibrostatic) collection capability. The models that produce super-hot air feed this up to the base of the sluicebox where there's a metal fan with an oscillating counterweight (see image below) that adds an additional shaking method to the process to help the heavier material to settle and even pass through the fine mesh. Most of the non-Vibrostatic models are a simpler system and are usually more compact. I've seen people in South America recover some pretty good gold with a bellows system and these are especially good in the Sierra/Nevada locations which are very dry.  All the Queenslanders I've spoken to who used a Dry-Washer were drying their soil out in advance in order to capture the fine gold beneath the mesh under the riffle-tray.


The counter-weight on the fan (which turns as the air flows from the motor) causes the entire lower portion of the sluicebox on a Dry-Washer to vibrate and oscillate... and this further helps the super-fine micron and submicron gold to pop between the gaps in the polyester mesh between and below the riffles.

I am pleased to see some reply s , it is what keeps this forum going.

Rowdy, I cannot remember if his name was Martin Marks . I only met him once , he was set up with his gear next to the Oallen Crossing . It included a car engine and automatic gear box . I heard later that he was advised to move his gear out of public view ... While I was talking to him at Oallen Crossing , James Henry Sturgiss drove up aged about 90 . There is a book written about his life , I have a copy . It is called The Man From The Misty Mountains .It is worth getting a copy and having a read ISBN 0 959381 3 6

nero_design wrote:

Nightjar wrote:Please explain:
Are you saying the fine/mustard gold passes through the riffle screen and collected in box underneath?????? Along with an even greater collection of electro magnetic dust - Iron stone and the like.v

The earlier models offered warm air from the motors but the hot-air models came later.  Keene have had around 8 varieties of Dry Washer, including several old-timer bellows systems (which are NOT suitable for submicron gold retention) which do not offer electrostatic (aka Vibrostatic) collection capability.

Totally disagree with your assumption about "Old Timer" bellows type Dry BLOWERS"
We operated two home built, engine driven bellows type Dry Blowers for many years and as previously mentioned out performed the Vibrostatic type dry blowers.
The mustard gold was always present when we brushed off the riffle box in preparation for wet sluicing. (Home built 12V recycable water sluices, more efficient than panning.)
When the riffle box was removed (about every hour) there was no more than a table spoon of dust collected under box. (We used a tight weaved cloth on the bellows Dry blower.)
The secret to efficient bellows type dry blowing was;
Dry feed.
Engine speed set so there was a steady flow of material over riffles. (Ran like a water, slight puff as it flowed over the riffles.)
Angle of riffle box was critical for flour gold retention.






***Note*** The series of round holes were positioned directly behind the "upside" of each riffle.

Minermike, if he had a car engine and gearbox setup then we are talking about 2 different people. There used to be a bloke at Oallen with a huge setup that he used a front end loader to feed it. I believe he was moved on by the authorities eventually.
Rowdy

Yes, I think I heard of the guy with a front end loader but I never saw it . Saw an American with a bit dredge at the " Big Hole " Powered by a Vee Dub engine , I think it was 8 inch . He told me that he had got 17 ozs. of gold. Heard that he took it to Q'land and later sold it to some guys who were going to use it to get tin . I think Pat was his name , had his family with him . Only here for a few months and then went back to the states.