target id mystery

[blazer35]

I was fooling around in my yard, and by the way my yard is covered with river stones, so I don't have to have grass to cut, and while hunting I had a target id of 90 or 91, so I cleared away the stones and dug it up, and it turned out to be an old piece of rusty metal, so I checked it with my anfibio on the ground without stones and it came up rusty metal or 08 or 09. I checked the area where I had the 90 reading and it's clear, no sound, now the stones didn't change anything so what's up, i'm sure there is a simple explaination ,but what?

 

[KindManTall]

"where I had the 90" <---- Hot Rock

 

[Cal_Cobra]

It's common for flat rusty tin, or iron to come in as a high conductor when in the ground. On the Multi Kruzer you can get some clues from the audio, but the TID can come in high as your target did.

 

[Big Treble]

That's falsing iron.

 

[Coin Rescue Inc]

Here is what I think

As steel or iron sit in the soil they rust up over time- making Iron Oxide
Sometimes this stains the soil around the object
Classic example is and old crown cap off a bottle or old nail. Did you ever dig one finding nothing but a big orange clump of rusty dirt?
I have read the Iron oxide (rust) makes a halo around the iron object over time providing the higher conductivity situation - thus the 90 -95 read out
I was also taught that if it was rusty iron and instead of digging, you gave it a good stomp with you foot the halo effect would break up and the high number signal would vanish and the lower number would prevail of no signal if Iron was discriminated out.
Thus proving if was iron falsing without digging.
Also this explains why the high signal disappears when you dig up the iron object. You disturbed the soil.

 

[jim tn]

Coin Rescue is 100 % right in my opinion. Quite often you can see the brown, rusty looking dirt in the darker dirt. HH jim tn

 

[D&P-OR]

CR is right on. Wet/damp ground makes it even worse.

 

[Phillip_in_NM]

Here is what I think

As steel or iron sit in the soil they rust up over time- making Iron Oxide
Sometimes this stains the soil around the object
Classic example is and old crown cap off a bottle or old nail. Did you ever dig one finding nothing but a big orange clump of rusty dirt?
I have read the Iron oxide (rust) makes a halo around the iron object over time providing the higher conductivity situation - thus the 90 -95 read out
I was also taught that if it was rusty iron and instead of digging, you gave it a good stomp with you foot the halo effect would break up and the high number signal would vanish and the lower number would prevail of no signal if Iron was discriminated out.
Thus proving if was iron falsing without digging.
Also this explains why the high signal disappears when you dig up the iron object. You disturbed the soil.

I've seen this idea presented many times - but yours is the best I've read ever. Thanks for sharing your insight!

 

[dgerst]

Bob the coil straight up and down over the dead center of the target. If the TID drops way down and you hear a lot of iron you can bet it's iron. If it stays solidly above say the 50's and only higher tones it's non-ferrous. Between that, sizing the target, and stomping or stabbing your digger to disturb the soil you can weed out almost all iron.