New Zealand Gold Prospecting & Metal Detecting Forums Archive

Okay I'm making a sluice and it's going to be a ripper. This is what I have got so far . A flange thing at the top with a piece of rubber sheet to smooth out the water, followed by vortex matting , then a drop riffle section and on top of all that I'm going to put a similar sort of thing to a bazooka gold trap at the end. Any ideas or things to make it better ? I don't want to mess around with pumps or anything like that though. All up it will be over a meter long made out of sheet metal.

Yep, couldnt agree more. Keep it simple.

The ribbed rubber mat at the head of the box is really just an indicator so you can see any gold passing over or the tiny bits getting caught up in it. It isnt there so much as a gold trap but just so you can see gold & know that the dirt you are putting down the box has gold in it. If it doeant then you need to dig else where.

As Simon said the flare is detachable & fits sideways in the box for a compact backpackable unit so you can get to those remote & hopefully, less flogged spots.



seperate flare


Box without flare attached




hinged riffle ladder




ribbed matting



riffle profile


Riffle ladder & bottom end with wing nuts that lock it down in place on the sluice box






Good luck out there

JW :)

Edited by user Monday, 19 November 2012 6:05:30 PM(UTC)  | Reason: Not specified

you will find that every river needs a custom box for the area i think if you are looseing gold still out the bottom end maybe your flow is to fast

i have in my box shallow verticals between the sloping riffles just to create more water movement

i was once concended that i was loosing gold out the bottom end so i made another box that fitted on the bottom end and gess what there was gold in it so i made another box so i now had three boes end for end and then there was no gold in the third box i find with my new system in the box 80% of my gold is recovered in the top third so set up the riffles correctly with not to much flow remember if gold can flow over the first riffle and all the riffles are the same then the gold will flow over the next and the next till out the bottom

i will try to down load a photo of my 3 boxes

heres a go

Hi Connor, lost gold out the end of a box is usualy down to the fact that the water velocity is too great. The water is doing the work of washing stuff down & out & it needs time to do this. People often over load there box & overwhelm it with too much material & choke up the riffles so they cant do there work properly & the gold can just skip over the top & on down the box. Or they have too greater slope &/or too much flow going down the box. They do this to get the water to wash on the bigger stones & rocks which saves them from having to man handle these out of the box themselves. Trouble is this will also wash on & out the finer gold. Some times the riffles are too high & need this stronger flow otherwise the stones & rocks cant get over them. Answer they think is to increase the flow when the right thing would be to reduce the size of the riffle & back off the water velocity so the finer gold can get a chance at settling out.
If your gold is pretty fine then you would be best with a larger type expanded mesh as a riffle system of its own .

Note the fine black sands caught up on the down stream side of the mesh & very little to no other stones & rubble & only with a very low water flow.


Great for fine gold recovery


Otherwise you could pre classify your material to say 10mm & less. I do this by using a sieve bucket & then feed this finer & greater concentration of paydirt material down the box.











It is a fine line between the right slope of the box & the velocity of water. You could also clean out your box more often.
Hope this is of some help to you

Happy hunting

JW :)

Edited by user Monday, 19 November 2012 8:01:20 PM(UTC)  | Reason: Not specified

Thanks for all the replys guys ! Yeah I'm sorry but 30 or more flake a pan ? I'm not moving ;)

Just casting my 2 cents worth... I like simple easy to use sluices. Mine has a good flare that channels the water creating a good flow of water running over ribbed rubber matting. I sometimes put expanded metal mesh over the top depending on the river and the type of gold present. I have several different types of matting that I use but the one I am most impressed with is Keene Miracle Matting. I find that running my sluice with high water velocity works best and I can run without having to pre-classify material. Rocks, gravel and sand all wash out leaving just black sand and gold.

Having water velocity too low is as bad as having water flow too fast through your sluice. If there is too much build up of material in your matting and in your riffles then there is nowhere for the gold to settle in behind the riffles or in the matting so it will just be washed out with the other gravels and sands. What I like to see is material "dancing" in the matting or behind the riffles. What that indicates is the light material is ready to be washed out of the sluice as you add more material. Your sluice is actively exchanging light material and trapping heavies.

I guess it comes down to experimentation with the sluice you run to find the optimum opperating flow/volume. Test your tailings for lost color and make adjustments. It is important that your matting and riffles clear of light material and that your sluice does not clog up. Happy sluicing.

The link below is a slideshow my sluice in action on the Shotover.

http://www.youtube.com/w...fGk&feature=g-crec-u