Can a detector find a target thru solids?

[matthias]

A couple places I hunt are dumping grounds for torn up concrete and asphalt with lots of dirt in the mix. Thickness ranges maybe 3" to 5". I appear to be getting strong target hits thru this solid material. Is this possible? HH. Matt

 

[Larry (IL)]

Sure, as long as it not solid metal. I have found many coins under old brick sidewalks.

 

[matthias]

SWEET! Thank you! Again...I can now go back and hit these targets again. HH. Matt

 

[REVIER]

Make sure you are not picking up pieces of re-bar.
Thick metal rods used to reinforce concrete.
Sometimes metal grids are used, also.

 

[thump7]

Make sure you are not picking up pieces of re-bar.
Thick metal rods used to reinforce concrete.
Sometimes metal grids are used, also.

Exactly what I was thinking.

Make sure you have the disc high enough to knock out re-bar if you are detecting through concrete.
If you have auto-ground balance would help too.

 

[TerraDigger]

As long as were discussing rebar...if you do sidewalk parkway grass strips...the more modern curbs may have rebar. In many old neighborhoods the grass strips are old, but the old curbs have been replaced with newer ones. You'll get fooled into thinking you have a coin up next to the curb. But rebar is easy to figure out by using higher discrimination.

 

[matthias]

After posting this question my roommate suggested I do an experiment and try this for myself. I did it. Yes the detector found the target thru 3.5" of asphalt with no problem. HH. Matt

 

[stasys]

and softs too

 

[matthias]

Right on stasys! HH. Matt

 

[osgood]

at an old estate I found a large cent under a huge sidewalk stone (probably about 3-4 inches thick). The stone itself was about 4 inches down and i near hurt my back flipping it. But went for it because my machine was giving a real solid signal through the stone and directly under the center of it. What they say above about rebar is true, sometimes sites have huge rebar laden hunks of concrete. Makes hunting quite difficult if you cant move the chunks around. CO

 

[matthias]

Thanks Curt! You are right. HH. Matt

 

[BarberBill]

I detected what I hoped was a buried treasure under a large, 6 inch or so, thick stone. Target gave a strong signal, but turned out to be an old ring gear from a car differential. Why it was hidden under the stone I'll never know, but it had me hoping for a few minutes.
BB

 

[Cliff KS]

Larry,

I was hunting an old farmhouse site where nothing was left of the house except the foundation and bricks from the chimney that had collapsed, because all the wood had been burned up when the subsequent owners burned the native pastures. I got signals from bricks that had become buried in the ground over the years. I finally picked up all the bricks on the surface and dug up all the whole bricks and pieces of brick that I got signals from, so I could hunt around the foundations without a barrage of signals. These bricks were old and seemed to be heavily mineralized. Did you get they same response from brick sidewalks? If so, how did you deal with it?

 

[Larry (IL)]

No, I don't have that problem with the bricks made here in Illinois.

 

[Steve O]

My first old coin was found under a 50 pound rock, 6" thick... it was a 1841 Russian 3 Kopeck in excellent shape.

 

[Hobo lobo]

Clay (bricks} that has been "fired" will detect, I have found piles of old indian pottery

 

[sheetal]

Yes, by using metal detector my coin was found under a rock.

 

[Shenandoah Digger]

You can't disc out the rebar and hear a good target beneath it. The disc control only cuts the audio for a target you do not want to dig. The detector still knows it's there. No such thing as iron see through. Not physically possible. The detector reports back the first target it sees, or closest to the surface. Can't see directly below it no matter how hard it tries.