Need help identifying best equiptment to be sure of gold coins under concrete

[1liquigirl]

My detector is identifying gold in an area under concrete inside Indian Caverns. The owner and I want to be sure it is gold coins before digging it up due to the fact that it is below quite a large amount of concrete and because of the damage factor that can occur to the cavern itself from vibrations in breaking up the concrete. The coins were hidden by the Robber David Lewis and would be worth millions in at least a fair state because they are rare. Sonar, Magnetometer, Ground Penetrating Radar, Infrared? What would be the best possible unit to use and identify what is under this concrete so we can be sure before digging? The owner and I have discussed looking into renting the proper equiptment to continue further in this search. If anyone has some information that can be useful or just a recommendation, please post a reply, or send me mail. Thanks a million ~Michelle

 

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[godisnum1]

I believe just a normal two-box detector will tell you all the info you're going to be able to get... it's just not going to tell you if the target is gold coins, specifically. I don't think you're going to be able to know for sure that there are indeed gold coins down there without destroying all the concrete... but why exactly is there concrete down there anyway?

Still, I think I'd be more concerned of the structural damage something like that might do to the cave system.

Bran <><

 

[Saturna]

A magnetometer is for ferrous metal like iron and steel.

If you have pinpointed your target with a metal detector, you don't have to break up all the concrete. Just drill some exploratory holes.
These will either bring up samples of whatever the metal is and/or allow a pinhole camera to be lowered down.
That seems the easiest and cheapest way to me.



Jay

 

[lamar]

Dear 1liquigirl;
A detector will not be able to discern what a cache is comprised of, merely what a cache is housed in. In other words, if a cache were housed in a tin box, then the detector would be able to discern the tin box, but not the contents within. Your best bet would be to verify the existence of the cache with another detector and compare results.

Then, if both detectors seem to show a favorable reading, a small hammerdrill and a 1/2" masonry bit can be used to drill a hole until the correct depth is almost attained, then the hole finished out by using a small sledgehammer and a masonry hand bit, so as to avoid the possibility of damaging the cache contents. Then, a borescope can be inserted into the hole and the void inspected for the possible existence of a cache, if any.

If the borescope verifies a cache, then the hole can be widened with a jackhammer and a sledge until the cache can be removed, and if there is no cache, then the hole can be filled in with concrete.

Go slow and try to verify all signals beforehand. Avoid drilling too many holes, as each hole drilled increases the chance of damaging coins, if there are any.
Your friend;
LAMAR

 

[Goodyguy]

Re: Need help identifying best equiptment to be sure of gold coins under concret

1liquigirl,

I have some experience with GPR (ground penetrating radar) Definitely can not distinguish gold from any other metal.

I think Lamar & Jay have the best ideas.

Who knows what non ferrous metal could have been thrown into the concrete for filler, maybe even aluminum soft drink cans or whatever could be giving a false gold signal.

However if you are sure its gold then it's worth the effort.
Follow Lamar's advice and you cant go wrong.

Buddy~

 

[1liquigirl]

Thanks for the replies so far. I just need something that will show the shapes of the metal objects under the concrete. We know it is coins we are looking for. Which of those will at least determine the shape?

 

[arkhunter]

drilling is your only choice

 

[G.I.B.]

You are certain there are no re-enforcing metallic attributes to the concrete itself?

If it is small, like a narrow walkway... how about cutting out a square panel section which can be lifted out of the way for the search. Then just set it back in when your done.

 

[Goodyguy]

Re: Need help identifying best equiptment to be sure of gold coins under concret

Thanks for the replies so far. I just need something that will show the shapes of the metal objects under the concrete. We know it is coins we are looking for. Which of those will at least determine the shape?

Are you saying that you believe the coins are not buried in some sort of container?
GPR is good at finding voids or shapes through concrete even picks out rebar. However I do not think it can distinguish shapes as small as coins.

Check this link it should answer your questions: http://www.geomodel.com/

Buddy~

 

[RelicHunterSantise]

Any thing new on this topic? I'd love to hear if you found something!!

xoxo

 

[1liquigirl]

going to go this week Tuesday or Wednesday to a smaller cavern below where the tourists go to metal detect there also. But pretty sure it's by the main entrance. The owner doesn't care if we just start drilling without GPR now. We'll cover up the patch with so much clay and gravel that no one will ever see the patch anyway. It's so close to being finished that, you can't even imagine my excitement. It's beyond what any metal detectorist could dream possible in the permission of any other owner. It's crazy. Thanks for your help guys, I'll fill you in as things continue. It's good. The Garett 250 Ace says all Silver ratings and high end Gold. All wiring ratings were blocked out including the wirings from the control box. Wish me luck

 

[AKiwi]

Re: Need help identifying best equiptment to be sure of gold coins under concret

You go Girl....Good Luck!

Cheers Paul

 

[1liquigirl]

Thanks Paul!!

Mr. Peabody, It reads 4 to 6 inches down. It is a 2x2 inch almost box shaped area. The concrete was poured in the 1920's and that was before they used rebar regularly. The owner assured us there wasn't any rebar put in and even if there was rebar in the concrete you would detect it throughout the caverns concrete flooring, not just in a square area. Thanks for filling me in on the depth issues with the Garrett though. That will help me in all future searches in other locations that are below 6 inches. I'll just dig it no matter what it may be if it reads at a depth of 6 inches or more. We'll be going out there in the afternoon tomorrow to check that lower cavern first, before the drilling and cover all the bases with the owner. Who knows, we might get a few tossed coins that tourists have thrown in that hole over the years, no one has been down there in decades. The owner said a guy spent his lifetime in search of the treasure and placed his set-up shop down in the room below the hole, probably because that was the most inconspicuous spot to be, it was back in the 1920's. There were remnants then of an old rope ladder, he had couches down there. The hole is smaller now due to steps they built in for the tours. I failed to ask the owner previously if they are still down there, but if they are we are going to search them too for any false bottoms or hiding areas to find retro stuff. I doubt that guy had a metal detector, or the archaeologists that were there in the 20's also. The concrete was placed in there after the archaeologists searched. The archaeologists were there digging up Indian artifacts due to stuff his family had found, some of which the owner's family was permitted to keep. They are in a display case in one of the cave rooms. The owner told me he knew that the archaologists never entered this lower room, so who knows what's going to be found. Wish me luck.

 

[ArkieGold]

Hey what's the latest? I hope you found gold!

 

[Goodyguy]

I am with you all the way Liquigirl don't give up til you find it.
Please take some pics of your finds and post them if you can.

 

[RELICDUDE07]

I hope its not just rebar,even the best detectors pick up large pieces of rebar .... "Rebar" is the steel reinforcing bar used in concrete construction. The term dates from the post-war American building boom of the 1950s, although reinforcing steel has been in use since the 1920s. Ridges are rolled into it as it's milled, to mechanically anchor it in concrete. Rebar is dark gray when new, rusty orange and scaly when exposed to the weather. Rent a 3 inch core drilling machine and you will have a clean hole in about 5 to 10 min...

 

[1liquigirl]

Okay all, sorry it took me so long to respond back to this post. We used a core drilling machine, packed rope to pull the concrete out, but didn't need it. There are videos on You Tube if you type in Indian Caverns in the Search Engine, there are 4 parts posted on there, but the camera guy posted mostly about himself and were being a little stupid and not professional. They left out most of the good metal detecting video footage on them, so I have to get back to him and take the time to pull the footage I want for a post on here. It ended up being what I think is a dynamite detonator piece. I have yet to put a pic on T-Net under catagory What Is It? With 2 jobs and the hobby, I don't have much time on T-Net, but I do my best. Anyone who wants to watch the footage he picked out is welcome to see it on You Tube, but it's mostly a bunch of rambling. Josh and I plan to go in the hole without all the rest of the folks on the videos, but he busted an ankle and won't be able to go with me there for a while. The video on that will be without all the confusion of this one, and much more professional. Thanks for your help, all of you from this post. ~Michelle