Gold in Sand and Gravel pits

[GoldReport]

Hi everyone!

Novice prospector here. I work for an aggregates mining company and have talked with the company geologist about gold in our s&g deposits. At my last site visits in Southern NY + NW PA I took my gold pan. I grabbed about a gallon of material from the sand screws and panned them. I would have done more material but was time limited. I did indeed find some glacial gold, really small stuff. What I am having a tough time figuring out is what processing this would look like. In my head I would set up a sluice box where the chute that feeds the sand screw is located. It would need to be something as low cost as possible and would not need to be cleaned out very often. Anyone have any pics of their setup they would be willing to share?

Still trying to determine the concentration in these deposits. If they could recover at least 0.01g per ton of sand, I think it could be profitable as an additional revenue stream.

 

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[Assembler]

Hi everyone! View attachment 2172642
Novice prospector here. I work for an aggregates mining company and have talked with the company geologist about gold in our s&g deposits. At my last site visits in Southern NY + NW PA I took my gold pan. I grabbed about a gallon of material from the sand screws and panned them. I would have done more material but was time limited. I did indeed find some glacial gold, really small stuff. What I am having a tough time figuring out is what processing this would look like. In my head I would set up a sluice box where the chute that feeds the sand screw is located. It would need to be something as low cost as possible and would not need to be cleaned out very often. Anyone have any pics of their setup they would be willing to share?

Still trying to determine the concentration in these deposits. If they could recover at least 0.01g per ton of sand, I think it could be profitable as an additional revenue stream.

Try processing say 1 - 2 tons will give you some target answers.

 

[GoldReport]

Try processing say 1 - 2 tons will give you some target answers.

Any recommendations on what equipment to use for a test of that scale? Would like to make the pitch to my boss to buy some gear if possible

 

[Assembler]

Any recommendations on what equipment to use for a test of that scale? Would like to make the pitch to my boss to buy some gear if possible

If the test is done first will help sell the idea of processing more.

 

[arizau]

Hi everyone! View attachment 2172642
Novice prospector here. I work for an aggregates mining company and have talked with the company geologist about gold in our s&g deposits. At my last site visits in Southern NY + NW PA I took my gold pan. I grabbed about a gallon of material from the sand screws and panned them. I would have done more material but was time limited. I did indeed find some glacial gold, really small stuff. What I am having a tough time figuring out is what processing this would look like. In my head I would set up a sluice box where the chute that feeds the sand screw is located. It would need to be something as low cost as possible and would not need to be cleaned out very often. Anyone have any pics of their setup they would be willing to share?

Still trying to determine the concentration in these deposits. If they could recover at least 0.01g per ton of sand, I think it could be profitable as an additional revenue stream.

Was your test panning done on raw product sand or on sand remaining in the screw trough after shut down?

 

[GoldReport]

Was your test panning done on raw product sand or on sand remaining in the screw trough after shut down?

It was on marerial left in the screw. What I didn't really see was grading (coarser/darker as you go down) in the sand in the corners. There were distint layers but not much that made me think it would be a good place for gold to settle out. And they had washed out the screw about two months prior so it was not a full year's worth

 

[arizau]

It was on marerial left in the screw. What I didn't really see was grading (coarser/darker as you go down) in the sand in the corners. There were distint layers but not much that made me think it would be a good place for gold to settle out. And they had washed out the screw about two months prior so it was not a full year's worth

Is the feed sand mostly dry or is it in slurry form?

 

[GoldReport]

Is the feed sand mostly dry or is it in slurry form?

Its a slurry coming off the bottom of a wash screen. The most obvious thing I can think of is to replace the feed chute with a sluice box. But not sure how well that would work. I also don't have a great idea on the cost, assuming this is a decent idea.

 

[Assembler]

Its a slurry coming off the bottom of a wash screen. The most obvious thing I can think of is to replace the feed chute with a sluice box. But not sure how well that would work. I also don't have a great idea on the cost, assuming this is a decent idea.

After processing a ton you will have a better answer.

 

[arizau]

Its a slurry coming off the bottom of a wash screen. The most obvious thing I can think of is to replace the feed chute with a sluice box. But not sure how well that would work. I also don't have a great idea on the cost, assuming this is a decent idea.

For what it is worth this is the way I see it for an inexpensive, continuous process:
The screw trough acts as a concentrator by creating a moving deadbed of slurry sand with the heavies migrating towards it's bottom. Figure out a way to cut a small stream of the slurry from the bottom center section of the trough near the discharge end and collect and deal only with those sands. Process with a gold cube or a beach sluice Is what I would try.

 

[GoldReport]

For what it is worth this is the way I see it for an inexpensive, continuous process:
The screw trough acts as a concentrator by creating a moving deadbed of slurry sand with the heavies migrating towards it's bottom. Figure out a way to cut a stream of the slurry from the bottom center section of the trough near the discharge end and collect and deal only with those sands. Process with a gold cube or a beach sluice Is what I would try.

That's certainly an interesting idea. Inexpensive is absolutely key. But before I do any of that will need to get a better handle on gold concentration.

 

[GoldReport]

After processing a ton you will have a better answer.

Any recommendations for equipment to process a ton efficiently? Very fine glacial gold in sand slurry which is basically 1/4" minus.

I want to sample the feed going into the sand screw while its running production. So I need to figure out a safe way to do that. And then my plan was to sample a 5 gallon bucket at a time and run it through a sluice (highbanker?) to get it concentrated and then repeat as quickly and efficiently as possible. I would need a way to record the weights of material as its coming, probably weigh up tailings if I could save them.

 

[Ohiogoldfever]

Being able to process in line is going to be a matter of the volume the sand screw is moving. If it were me I would grab a used high banker and run about a ton through it. That should give you a decent sense of what you’d expect.

As a guy who works glacial gold I would have a feeling the people in charge would have a hard time justifying the investment for the machine needed to process more than a couple tons an hour.

Just a guess though.

 

[Assembler]

Any recommendations for equipment to process a ton efficiently? Very fine glacial gold in sand slurry which is basically 1/4" minus.

I want to sample the feed going into the sand screw while its running production. So I need to figure out a safe way to do that. And then my plan was to sample a 5 gallon bucket at a time and run it through a sluice (highbanker?) to get it concentrated and then repeat as quickly and efficiently as possible. I would need a way to record the weights of material as its coming, probably weigh up tailings if I could save them.

The high banker would be good. So would a gold cube.
The main thing is to show a reasonable return on time spent.

 

[GoldReport]

Being able to process in line is going to be a matter of the volume the sand screw is moving. If it were me I would grab a used high banker and run about a ton through it. That should give you a decent sense of what you’d expect.

As a guy who works glacial gold I would have a feeling the people in charge would have a hard time justifying the investment for the machine needed to process more than a couple tons an hour.

Just a guess though.

I appreciate yours and others' responses. I suppose for now I will just focus on getting more material sampled. We have lots of other sand and gravel plants in the US so hoping to take lessons learned here and apply elsewhere.

I'm currently building my own highbanker, mostly just for fun, and that may be the tool I take with me next time I'm out there.

 

[Assembler]

Any recommendations for equipment to process a ton efficiently? Very fine glacial gold in sand slurry which is basically 1/4" minus.

I want to sample the feed going into the sand screw while its running production. So I need to figure out a safe way to do that. And then my plan was to sample a 5 gallon bucket at a time and run it through a sluice (highbanker?) to get it concentrated and then repeat as quickly and efficiently as possible. I would need a way to record the weights of material as its coming, probably weigh up tailings if I could save them.

The number of 5 gallon buckets can add up to a volume that you could show your boss. If there is little push back maybe add a augur feed to your high banker for a much bigger run of materials?

 

[russau]

To process this material while the plant is running , you would need a large piece of equipment so you wouldn't slow down plant operations ! I had the very same idea 20 years ago while we were on a club outing . A club member operated several dump trucks out of a sand & gravel plant and they wanted to know if there was any gold in it. My answer was , heck yes there is !and I showed them how to do it. The sand screw they had was a 4 foot incline screw and we test panned several large piles of various sized sand and they had fine gold in every one of them, then I turned around and pointed to that sand screw hopper and said there's where the gold will be and I asked if I could get in the hopper to poke around?? they were down for the weekend and I got in and there was 3 or 4 foot of mostly black sand !I dipped my gold pan into and got some small amount of B.S. and it had LOT'S od fine gold in it. I showed it to the foreman and he said we could have all of that B.S. we wanted as long as they were down. I wanted to get my 2 inch Proline dredge in there to suck out that sand and stick the end of the dredge out of the exit hole for the hopper but it wasn't with me so we just got as many 5 gallon bucket's we could find and let her lose !MESSY, YES but we got a lot of material ! and YES them buckets were REALLY HEAVY !!!!!!!!!! At one of our first club meetings we had I offered everyone that signed up to our club a 3 Lb. baggie of these super cons ! We ran out of cons but more people wanted to join ! I can't remember but I think we gave away at least 40 bags of cons. When the temp dropped they would open that exit access door and dump the sand back into their sump and it was washed back into their pond to keep from freezing and cracking the equipment.

 

[GoldReport]

To process this material while the plant is running , you would need a large piece of equipment so you wouldn't slow down plant operations ! I had the very same idea 20 years ago while we were on a club outing . A club member operated several dump trucks out of a sand & gravel plant and they wanted to know if there was any gold in it. My answer was , heck yes there is !and I showed them how to do it. The sand screw they had was a 4 foot incline screw and we test panned several large piles of various sized sand and they had fine gold in every one of them, then I turned around and pointed to that sand screw hopper and said there's where the gold will be and I asked if I could get in the hopper to poke around?? they were down for the weekend and I got in and there was 3 or 4 foot of mostly black sand !I dipped my gold pan into and got some small amount of B.S. and it had LOT'S od fine gold in it. I showed it to the foreman and he said we could have all of that B.S. we wanted as long as they were down. I wanted to get my 2 inch Proline dredge in there to suck out that sand and stick the end of the dredge out of the exit hole for the hopper but it wasn't with me so we just got as many 5 gallon bucket's we could find and let her lose !MESSY, YES but we got a lot of material ! and YES them buckets were REALLY HEAVY !!!!!!!!!! At one of our first club meetings we had I offered everyone that signed up to our club a 3 Lb. baggie of these super cons ! We ran out of cons but more people wanted to join ! I can't remember but I think we gave away at least 40 bags of cons. When the temp dropped they would open that exit access door and dump the sand back into their sump and it was washed back into their pond to keep from freezing and cracking the equipment.

Did you notice any size of sand had more gold in it? The plant I want to spend my time at makes a couple different types of sand. The first is a typical concrete sand, second is a manufactured sand which is made from crushed products I don't think this will hold much gold, third is "mason sand" which is made off the overflows of the other two larger products. And of course there is the material going to the silt pond. I would preferentially sample material prior to it going to the concrete sand tank because I think gold is getting floated out due to it being so stinkin' fine. But that option seems difficult as its a fast flowing chute with lots of water and sand flowing down it. Something like 100-150 tph of sand plus the water.

The easier option would be to sample material from the stockpiles, this might be what I do since it will be the easiest to access while the plant is running.

When they shut the plant down and drained their sand tank I did notice a lot of black sand streaking out and got a couple trowels of that in my original test. That might be where I found the gold initially but hard to tell.

It seemed like the heavies weren't really accumulating in the bottom of the tank, the material was really packed down and I don't suspect much gold would settle into it. But I could be wrong as I happen to be from time to time...

Also, I saw your tag is for Missouri. Have you found gold in Missouri? We have a sand plant down there and the deposit they are mining is from an old riverbed of the Mississippi

 

[Assembler]

Did you notice any size of sand had more gold in it? The plant I want to spend my time at makes a couple different types of sand. The first is a typical concrete sand, second is a manufactured sand which is made from crushed products I don't think this will hold much gold, third is "mason sand" which is made off the overflows of the other two larger products. And of course there is the material going to the silt pond. I would preferentially sample material prior to it going to the concrete sand tank because I think gold is getting floated out due to it being so stinkin' fine. But that option seems difficult as its a fast flowing chute with lots of water and sand flowing down it. Something like 100-150 tph of sand plus the water.

The easier option would be to sample material from the stockpiles, this might be what I do since it will be the easiest to access while the plant is running.

When they shut the plant down and drained their sand tank I did notice a lot of black sand streaking out and got a couple trowels of that in my original test. That might be where I found the gold initially but hard to tell.

It seemed like the heavies weren't really accumulating in the bottom of the tank, the material was really packed down and I don't suspect much gold would settle into it. But I could be wrong as I happen to be from time to time...

Also, I saw your tag is for Missouri. Have you found gold in Missouri? We have a sand plant down there and the deposit they are mining is from an old riverbed of the Mississippi

Is there any way you can take a small skid front loader (Bobcat etc.) into the test areas to remove a few tons of BS materials for each test?

 

[GoldReport]

Is there any way you can take a small skid front loader (Bobcat etc.) into the test areas to remove a few tons of BS materials for each test?

I'm not sure I follow what you mean. The site is your typical aggregates plant with stackers for each of the product piles. If I sample these I will likely try to sample from the back side of the stockpile where the heavier material would fall. I could definitely get a loader in to move some material if needed