Iron bottle caps

[coach c]

On my GTI 2500, old flattened bottle caps give a bell tone and read as dimes. Why would something made out of iron read as silver?

 

[Gold Buddy]

n/t

 

[Joel-Winnipeg]

Shape and rusty may signal different.
Angle in the ground.
If the cap is bent or squeezed smaller
depth can also be an influence
Metal composition .

 

[ojm bc]

n/t

 

[ojm bc]

n/t

 

[NM5K]

Rust is fairly highly conductive, and lots more conductive than the original
iron the cap was made from. Lots of times, you'll bounce around and hit
both ends of the scale, reading both the rust and the iron.
The more rust, the hotter it's gonna bang most of the time.
The machine is working fine. It just can't tell the difference being
both the real coin and the rusty cap are showing the same appx
conductivity.
Nails and other iron stuff will act the same way.

 

[ojm bc]

n/t

 

[Uncle Willy]

How high are you running your sensitivity when you get these signals?

BIll

 

[coach c]

Bill......I have been running sensitivity at 7 for awhile. At this site, all the bottle caps are flattened out and completely rusted. I guess it's the rust reading high. I am learning. Still too impatient to dig everything.

Why are there so many cans at a depth that the indicator max's out? Do cans sink deeper and faster than coins?.....Coach

 

[Uncle Willy]

Run it a 6 and see what happens and keep your coil of the ground an inch or so. Garrett coils don't take too well to "scrubbing.". A lot of people bury the cans rather than look for someplace to dispose of them. I find lots of them in bark chip playgrounds buried three or four inches down. At beaches people will bury them..

Bill

 

[Mick in Dubbo]

Cans are fairly easy to figure out. If you lift your coil more than 6 inches and it's still giving a signal, then it's not a coin. Also, when pinpointing, you will notice that coins signal drops off fairly quickly when they pass under the edge of the inner coil. Cans take a fair bit before the signal fades. Same as any large object in the ground.
Mick Evans.