Former Opencast Site???

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Pete E
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I have permission to detect over two large fields that was an Opencast mine in the 1950s/60s, but was subsequently restored to pasture...

My natural inclination is to give it a miss, but should I view it as detecting over spoil heaps on a huge scale??

I would be very interested in hearing people's thoughts on this, or even better, if they have any experience detecting, this sort of ground???
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Emily
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Pete E wrote: Fri Apr 30, 2021 9:40 pm I have permission to detect over two large fields that was an Opencast mine in the 1950s/60s, but was subsequently restored to pasture...

My natural inclination is to give it a miss, but should I view it as detecting over spoil heaps on a huge scale??

I would be very interested in hearing people's thoughts on this, or even better, if they have any experience detecting, this sort of ground???
Whats an opencast mine??
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Pete E
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Emily wrote: Fri Apr 30, 2021 9:53 pm Whats an opencast mine??
Hi Emily,

It's an alternative mining method used to extract coal when the seam is near the surface.

Basically they remove the top soil over a huge area, and then use earth movers to scrape away layers of soil until they reach the coal, which is then dug out. Once all the coal is extracted, they then reverse the process, and landscape the area restoring it to roughly its previous shape before spreading the heaps of saved top soil back on and then reseeding it with grass..

Sometimes, they will refill the open working with rubbish using it as a land fill site, before again putting the top soil back and reseeding to grass..

From a detecting point of view, all the historical layers in the soil are well and truly mixed up, with artifacts being buried feet down, but also potentially many deep objects being redeposited at detectable depths, at least in theory anyway...
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Oxgirl
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It depends what they used to refill it with I guess. I look at the thousands of tonnes of building site topsoil that is removed and redeposited somewhere else and would love to get my hands on those fields :Party:
Yes I really don’t like Roman coins, I’m not joking
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Easylife
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Anywhere at all should not be dismissed without at least giving it a fair go. The soil that was brought in to infill can be from a site with much greater history. There is only one way to find out!
I was offered a large local site where gravel had been extracted and then made good, but it just didn't feel very appealing so I never tried it, and probably never will! :D :thumbsup:
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coal digger
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It's hard work but if it's the only spot you have then worth a go. The bi product of coal dust,slag mixed with the soil turns it black and sends the machine into a flat spin.
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Pete E
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coal digger wrote: Sat May 01, 2021 9:32 am It's hard work but if it's the only spot you have then worth a go. The bi product of coal dust,slag mixed with the soil turns it black and sends the machine into a flat spin.
It's not the only place I have but given its consists of a couple of very large fields on one particular farm, I may give it a go...
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figgis
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Got to be worth a butchers, Pete. I recall reading elsewhere about topsoil being brought in from outside and put onto a field and it turned out to be stuffed with Roman finds
Reiver
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If you have it as a permission , search it !
Even if it's a cursory spin over the site you have to do it. You never know!
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Easylife
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figgis wrote: Sat May 01, 2021 3:34 pm I recall reading elsewhere about topsoil being brought in from outside and put onto a field and it turned out to be stuffed with Roman finds.
Everyone was avoiding the filled in pond on a rally and not much was showing until someone tried it.
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Emily
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Pete E wrote: Fri Apr 30, 2021 11:06 pm Hi Emily,

It's an alternative mining method used to extract coal when the seam is near the surface.

Basically they remove the top soil over a huge area, and then use earth movers to scrape away layers of soil until they reach the coal, which is then dug out. Once all the coal is extracted, they then reverse the process, and landscape the area restoring it to roughly its previous shape before spreading the heaps of saved top soil back on and then reseeding it with grass..

Sometimes, they will refill the open working with rubbish using it as a land fill site, before again putting the top soil back and reseeding to grass..

From a detecting point of view, all the historical layers in the soil are well and truly mixed up, with artifacts being buried feet down, but also potentially many deep objects being redeposited at detectable depths, at least in theory anyway...
Thank you for explaining. I now understand the meaning. ☺️ You might as well search it. If it’s no good, you don’t go back, but you never know. ☺️
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coal digger
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Pete E wrote: Fri Apr 30, 2021 11:06 pm Hi Emily,

It's an alternative mining method used to extract coal when the seam is near the surface.

Basically they remove the top soil over a huge area, and then use earth movers to scrape away layers of soil until they reach the coal, which is then dug out. Once all the coal is extracted, they then reverse the process, and landscape the area restoring it to roughly its previous shape before spreading the heaps of saved top soil back on and then reseeding it with grass..

Sometimes, they will refill the open working with rubbish using it as a land fill site, before again putting the top soil back and reseeding to grass..

From a detecting point of view, all the historical layers in the soil are well and truly mixed up, with artifacts being buried feet down, but also potentially many deep objects being redeposited at detectable depths, at least in theory anyway...
I've done my fair share st the seam edge with a pick getting the black gold out where the machines couldn't get to One site we came accross loads of small wooden shaft supports made by children a good 200 yrs ago😔
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Pete E
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coal digger wrote: Sat May 01, 2021 10:27 pm I've done my fair share st the seam edge with a pick getting the black gold out where the machines couldn't get to One site we came accross loads of small wooden shaft supports made by children a good 200 yrs ago😔
Bit off topic but my late father started work at the local pit while still a school boy. At 14, he left school to work in the mines full time and hated it...Due to war time restrictions and continued coal rationing after the war he had to stay there until he found work in the building trade in his early 20s...
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Ladybird66
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One place I had permission to detect were they were making an outdoor Ménage for the daughter. That was built up with soil brought in from somewhere else.
Best thing I ever found on that farm was a lovely Victorian silver bar brooch with BABY stamped on it in the top soil.
Thing is, you don’t know where it’s come from. Always worth a go. Plus it’s usually easy digging :thumbsup:
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Always worth a go. The open cast will have been restored using the waste rock and spoil from the mine, but topped off with topsoil so the grass would grow and the land be reused for agriculture. That topsoil will have come from the original stripping of the site and stored for restoration. Sometimes topsoil from elsewhere will have been added to complete the job and along with it any small finds.

In the 80's when the Jorvik digs were active in York it is rumoured that the spoil from there was used as cover for a local landfill site. Naturally the spoil was never detected so all the small finds that were missed would have ended up on top of a few million tons of household waste.

As another example a large road construction site near to me has recently had the areas used for gravel borrow pits restored and the general environs of the offices and construction stores/production sites covered with the spoil taken from the many extensive archaeological excavations that also took place prior to construction. Hence all the out of context archaeological small finds from the machine stripping of the top and subsoils plus that from the general engineering works will be in this material.

Let us all know how you get on.
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