Question About Making An Artificial Crevice In A Clay Bottom Stream

[flinthunter]

I'm doing some panning in a stream in Central Illinois and having a small amount of luck. The stream bed is mostly glacial sand and gravel but there is the occasional strip of bare solid clay.

I am thinking about using a spade to dig several artificial crevices/trenches in the clay that would run across the stream. Do you think this might capture some gold and if so, what are your recommendations for the depth, width, and angle of the trench sides (straight or tapered sides).

I've never read about anyone doing this and am looking forward to your opinions. Thank you.

 

Amazon Forum Fav 👍

Family Maps of Hinds County, Mississippi, Deluxe Edition - Grab it through Amazon!

[russau]

If the property is on your land or land that you have permission to be on then Id say , go for it! you never know until you try! As far as the dimensions of this homade crevice that would really depend on the streams speed and volumn of water and the thickness of the clay! if that clay layer isn't thick enough , it will peel apart during heavy water flows (floods)

 

[flinthunter]

If the property is on your land or land that you have permission to be on then Id say , go for it! you never know until you try! As far as the dimensions of this homade crevice that would really depend on the streams speed and volumn of water and the thickness of the clay! if that clay layer isn't thick enough , it will peel apart during heavy water flows (floods)

It is on land I have permission to be on. This is a 5 to 6 foot thick layer of very hard Pennsylvanian era blue clay that was once the ancient sea bed that covered this area. It holds together very well under large volumes of water. The stream flow under normal conditions is 15 to 20 feet wide and averages about a foot deep. After a super heavy storm I've seen it 10 feet or more deep. Thank you for your input.

 

[goldenIrishman]

I'd agree with Russ. If you own the land or have permission... Go for it!!!!

Now if I was to try something like what you're asking about, I'd make the crevices in several different sizes and shapes to see what works best. Since natural crevices are like Mother Natures version of a drop riffle sluice, look at designs for them to get ideas for different ways to make them. If you can find a place where the stream flattens out, I'd go on the upstream end to start with. Keep us posted if you give it a try!

 

[meMiner]

I like the responses and would be interested in how it works out. However, I suspect that if you can make it with a spade, then the rush of water necessary to move gold will likely tear your riffle apart. For sure, if you dig a trench, mark it above the bank somehow so you can find it again even if it fills back in.

 

[Reed Lukens]

Sounds like a lot of work and hard clay breaks the way it wants to... Personally, if it's hard clay a spade won't touch it. You will need a pick and even then it's not going to be fun, soooo. Take a toothed backhoe down and make a couple scrapes across the river as deep as you can to make complete riffles in it. My personal experience with deep hard clay is that it will not cut straight with a pick. If you could drain the water off and use a circular saw or a saws-all, you could do it by hand with a pry bar. You can see the deep clay in this river we work, it's up the sides as well as all the way across. I don't know how deep it goes but it's actually a false bedrock with a great pay layer underneath it.

 

[flinthunter]

I'd agree with Russ. If you own the land or have permission... Go for it!!!!

Now if I was to try something like what you're asking about, I'd make the crevices in several different sizes and shapes to see what works best. Since natural crevices are like Mother Natures version of a drop riffle sluice, look at designs for them to get ideas for different ways to make them. If you can find a place where the stream flattens out, I'd go on the upstream end to start with. Keep us posted if you give it a try!

I like your ideas. Thank you.

 

[flinthunter]

I like the responses and would be interested in how it works out. However, I suspect that if you can make it with a spade, then the rush of water necessary to move gold will likely tear your riffle apart. For sure, if you dig a trench, mark it above the bank somehow so you can find it again even if it fills back in.

I'm not sure if the spade will cut it or not. I am planning on bringing the pick also. Thanks for your input.

 

[flinthunter]

Sounds like a lot of work and hard clay breaks the way it wants to... Personally, if it's hard clay a spade won't touch it. You will need a pick and even then it's not going to be fun, soooo. Take a toothed backhoe down and make a couple scrapes across the river as deep as you can to make complete riffles in it. My personal experience with deep hard clay is that it will not cut straight with a pick. If you could drain the water off and use a circular saw or a saws-all, you could do it by hand with a pry bar. You can see the deep clay in this river we work, it's up the sides as well as all the way across. I don't know how deep it goes but it's actually a false bedrock with a great pay layer underneath it.

View attachment 1247405

Thanks for your reply. I'm aware that this may not work but all I'm going to be out of is my time and labor. At least I can say I tried.

 

[stefen]

Instead of making false crevices on the clay layer, which may be readily destroyed by seasonal storm runoff, perhaps using old fashioned methods like carpet material or sheep skins to catch passing gold?

 

[flinthunter]

Thanks stefen, that's a thought also

 

[Reed Lukens]

Or use a chainsaw to cut the riffles into it, the bar will be oiled by being under water. You would just have to keep the motor above water and probably just use an old blade being it's clay and then toss the blade when you're done. I used to have a chainsaw dedicated for cutting up a moose. I always put vegetable oil in it. I would think that the water, even though it's not oil, would cool and lubricate along with splashing all over you but... it's a new brainstorm for cutting clay. I have a spot that I've been pondering on for years and blasting just makes a mess and cracks the clay to pieces... huge pieces that still have to be broken out with a 6' pry bar in order to move them.

 

[flinthunter]

Or use a chainsaw to cut the riffles into it, the bar will be oiled by being under water. You would just have to keep the motor above water and probably just use an old blade being it's clay and then toss the blade when you're done. I used to have a chainsaw dedicated for cutting up a moose. I always put vegetable oil in it. I would think that the water, even though it's not oil, would cool and lubricate along with splashing all over you but... it's a new brainstorm for cutting clay. I have a spot that I've been pondering on for years and blasting just makes a mess and cracks the clay to pieces... huge pieces that still have to be broken out with a 6' pry bar in order to move them.

It's a thought, thanks. I've got a couple old chainsaws around that I don't use anymore. I may try that.

 

[rockbar]

Instead of cutting your riffles into the clay, you might consider bolting down some lengths of angle iron into the clay. Just another way to skin the cat.

 

[flinthunter]

Thanks rockbar. A lot of interesting ideas here.

 

[Duckshot]

I read about this somewhere, someplace. The way I remember, the first sluices were just a diversion of the stream over riffles made of dirt in a trench. A little later they started using wood riffles in a trench, and then somebody got the bright idea to make a trench out of wood so they could carry it around.

If it's legal, what I would try is to make some "L" or maybe inverted "T" shaped flexible wooden riffles and stake them down to the stream bed. The wood could bend tight to the stream bottom or better just slightly below the bottom.

 

[Reed Lukens]

The problem with trying to stake anything to the bottom of a river is that it takes not only the right bedrock but it also has to be facing the right direction. Clay unfortunately cracks and crumbles when anything is driven or screwed into it. It's just too soft and is most definitely the hardest to work because when you try to open up cracks, many times they just crack deeper.

 

[MadMarshall]

The notion of making an artificial crevice is entertaining at best. Takes a lot of circumstances for gold to be moved and deposited one of the biggest bien time and extreme events... so unless you are planning on making an artificial crevice now and then goin to check it fifty years later and even then there is no guarantees that gold will even be there I doubt this idea has any merit. Its fun to think about in the way its fun to think about a pot of gold at the end of the Rainbow. Lots of good reading on sediment transport on the internet..

 

[ohiochris]

I have read somewhere on the internet about making gold traps to put on a creek bottom , I cant remember where I read about it but it is something that people do. Something like this would be more effective in an area with more gold potential and larger gold though. I have a nearby stretch of creek here in Ohio that is gravel on top of a clay layer so thick Ive never been able to get through it. As I scrape thin layers off the clay to look for gold I leave lots of ridges and cuts in it that should catch gold but so far in three years it never has that I have seen. The small gold we have takes so long to wash into the water and reach its settling point , and there is so relatively little of it , most of what we are finding now has usually been there for a very long time. It may take many years for artificial gold traps to catch anything in our relative area. Thats not saying it wouldnt work , only that it may be like finding a needle in a haystack. Couldnt hurt to try though.

 

[Goldwasher]

Passive gold traps don't work for the same reason mad Marshall explains. If you were going to put a trap in a creek you would need to know if there was a deposit upstream affecting gold deposition in that area....if you have that knowledge and don't take advantage of it maybe you shouldn't be prospecting. Hoping that gold is just going to end up in a spot every season pretty hopeful.