Question regarding flow rate for sluice

[DMann1987]

Hello fellow gold prospectors!

I usually try to use my GoldHog River Sluice in the actual river, but sometimes the current is just not sufficient. I bought a 12v 1100 GPH pump to attach to my sluice. The GoldHog sluice came with a low flow and high flow mat. Is 1100 GPH considered "high flow"? I know incline of my sluice also determines the flow rate, I usually don't have it too inclined when in the river, just enough to get things moving. With the pump setup I can pitch it more.

Any insight would be appreciated, thank you all!

 

Amazon Forum Fav 👍

Cry Of The Eagle: History And Legends Of The Cherokee Indians And Their Buried Treasure - Grab it through Amazon!

[ConceptualizedNetherlandr]

Hello fellow gold prospectors!

I usually try to use my GoldHog River Sluice in the actual river, but sometimes the current is just not sufficient. I bought a 12v 1100 GPH pump to attach to my sluice. The GoldHog sluice came with a low flow and high flow mat. Is 1100 GPH considered "high flow"? I know incline of my sluice also determines the flow rate, I usually don't have it too inclined when in the river, just enough to get things moving. With the pump setup I can pitch it more.

Any insight would be appreciated, thank you all!

I am no expert, but you might mean pitch it less. Less slope if you increase the water flow by adding a pump. Or do you mean only the pump and run it less that the river flow?

One way to test your setup is to first decide what is smallest gold particle you plan to recover.
Then get some material - like quartz sand - which you size select to be 6 times as large as your smallest gold. drop a little in the feed and see if it is mostly retained. If it washes out so will your gold.

 

[DMann1987]

I am no expert, but you might mean pitch it less. Less slope if you increase the water flow by adding a pump. Or do you mean only the pump and run it less that the river flow?

One way to test your setup is to first decide what is smallest gold particle you plan to recover.
Then get some material - like quartz sand - which you size select to be 6 times as large as your smallest gold. drop a little in the feed and see if it is mostly retained. If it washes out so will your gold.

Thank you for the advice! Yeah, I plan to only use the pump instead of the stream since there isn't much flow at all right now. Pitch is what I meant, thank you. That's a great idea. Would the same principle apply if I tested it with black sand to see if the sand is retained and then go through the tailings to see if any (& how much) slipped through? I have plenty of black sand I could run. I do also have gold that I've recovered that I could run through to see if it collects it. Great idea. The area I'm working primarily has smaller sized gold pieces but in decent quantities so I'd like to capture the smaller ones too. There's larger pieces as well but primarily smaller. Not fly poop size but pretty small.

 

[ConceptualizedNetherlandr]

Any material would work providing you size it correctly for it's specific gravity ratio to gold. Your black sands might not be of uniform mineralogy. The key is to figure what size gold you are ready willing and able to successfully clean up*. Use screens to size accurate. Then use larger screens ( based on density ratio) to create your uniformly sized ( and hopefully uniform specific gravity) test material.

The more precise the better, but using 5.2 to 6(?) for your blacks and 19.3 ( if your gold is pure) gives you about 4x for your test material.

You sorta need to know the density of your test material to size it right. I chose quartz ( silica ) sand in that example because it has a known density and is easy to find or even make. Crush & screen. Of course that varies in nature as well, even in glass. Keep in mind you do not know the purity of your target gold either. Well drilling suppliers sell graded clean silica sands.

This is why we take home concentrates and finish it under more controlled conditions. If you run your sluice clean of everything but gold you have let most it pass right off the end.

*Take your gold you already have. Determine by running through screens what size is retained on the smallest screen. After that nothing matters because you have not yet been able to successfully process that from stream bank to jar. If that is not much % of your total gold, move up your screen sizes until you have an acceptable take at the small size. Might as well be cost effective and achieve an ROI. Calculate your test size ratio based on that. Why waste your time with anything smaller if it will not put much gold in your jar at the end of the journey?

If there is no risk of missing a nugget (pick that size for each place you hunt ) classify the living daylights out of your feed stream into the sluice and run it like a precision machine. You can always pour out the oversize and detect it.

Size matters. Hydraulic separation is about size and density. The more uniform size the better the density separation. Conversely with density and size, but what is the point of that?

Go a bit smaller if you think that in the future you will want to process your old waste concentrates for finer gold. I play with various hydraulic separation inventions and I'd love to have a crack at peoples waste concentrates.

 

[DMann1987]

Any material would work providing you size it correctly for it's specific gravity ratio to gold. Your black sands might not be of uniform mineralogy. The key is to figure what size gold you are ready willing and able to successfully clean up*. Use screens to size accurate. Then use larger screens ( based on density ratio) to create your uniformly sized ( and hopefully uniform specific gravity) test material.

The more precise the better, but using 5.2 to 6(?) for your blacks and 19.3 ( if your gold is pure) gives you about 4x for your test material.

You sorta need to know the density of your test material to size it right. I chose quartz ( silica ) sand in that example because it has a known density and is easy to find or even make. Crush & screen. Of course that varies in nature as well, even in glass. Keep in mind you do not know the purity of your target gold either. Well drilling suppliers sell graded clean silica sands.

This is why we take home concentrates and finish it under more controlled conditions. If you run your sluice clean of everything but gold you have let most it pass right off the end.

*Take your gold you already have. Determine by running through screens what size is retained on the smallest screen. After that nothing matters because you have not yet been able to successfully process that from stream bank to jar. If that is not much % of your total gold, move up your screen sizes until you have an acceptable take at the small size. Might as well be cost effective and achieve an ROI. Calculate your test size ratio based on that. Why waste your time with anything smaller if it will not put much gold in your jar at the end of the journey?

If there is no risk of missing a nugget (pick that size for each place you hunt ) classify the living daylights out of your feed stream into the sluice and run it like a precision machine. You can always pour out the oversize and detect it.

Size matters. Hydraulic separation is about size and density. The more uniform size the better the density separation. Conversely with density and size, but what is the point of that?

Go a bit smaller if you think that in the future you will want to process your old waste concentrates for finer gold. I play with various hydraulic separation inventions and I'd love to have a crack at peoples waste concentrates.

Wow thank you for the super detailed reply. Truly appreciate the advice and time you spent writing it up! It'll definitely help me tomorrow when I go back out there. Thanks again!

 

[Flatline]

Id say that if you run it correct your losses will be so small it doesn't matter how well you test things. What you just need to do is to know roughly how big the biggest gold will be then screen it down to that but look in the screen just to not miss any larger pieces. Then if the material is dancing in the riffles and they clear out most of the less dense material but gold and some black sand and some stones stay you are good to go. You're not gonna get every single spec so trying to over optimize the recovery rate is just a waste of time, then it's better to just shovel more material through it. Sure if it was a big operation it would be more important to try to get every spec..

 

[russau]

I think you need to concentrate on the smaller gold specks , the larger pieces will take care of themselves! Most of the gold we find is the smaller size . And everywhere I went I find conditions are different so I brought with me various options of screens / riffles / and mats to setup my dredge's and sluices to accommodate the size of gold that I hope to capture !