War Nickel Testing

[Nick A]

Just thought folks would like to see this. I tested 33 war nickels and the results varied quite a bit.

1 read 12-14
5 read 12-15
12 read 12-16
10 read 12-17
4 read 12-18
1 read 12-19

I know air testing is biased, but knowing the range these vary by may be helpful.
Unfortunately these run directly into pulltab territory.

 

[TheMarshall]

Hello Nick.........thanks for your post.

Thoughts:-

I'm not sure what you mean by "Air testing is biased"?

The only bias is the indefinite wave of the hand, so to speak.

Air testing is just that....very specific in definition, and only as variable as the tester's manual dexterity regarding results.

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Silly people decry air testing....They are ignorant and lack simple comprehension of exactly what it implies.

Would the same people tell you that wind tunnel testing of an aeroplane's wing is useless or meaningless?

Forget the 'wallies',,,,,, air testing is a valid exercise.

It tests the VDI calibration in 'space',,,,,, a medium with a magnetic permeability of 4 x PI x 10 to the power of minus 7.

[size=large]THAT IS HOW YOUR DETECTOR IS CALIBRATED[/size]

'Air' is a 'constant' compared to universal ground conditions, so you can't 'calibrate' a metal detector's VDI responses in such a medium as ground.

In the ground, the soil's magnetic permeability is increased several fold, as dictated by the Fe mineralisation.

The conductivity of the soil also affects the VDI, but it is the magnetic factors, depth and other local artifacts, that adds most variations to the resulting VDI.

Your set of data provides an average conductivity factor of 16.5 for the group of coins tested i.e. Fe12---Cond 16.5.

As you are well aware, it is the Fe of the target that is most vulnerable to variation when in the ground.

Hope you are enjoying your detector...........TheMarshall

 

[Nick A]

What I mean when I say biased is that these same coins may not read the same in the ground as they did in the air test. Also my detector is not the same as everyone else's. Your E-Trac may read these same coins differently. The one interesting thing I get from this is that ground effects aside, the coins themselves have a certain amount of variability, even before we add the "in ground" factors. Which means that even across detectors these coins would have the same range of variability in the readings.

 

[Elton]

Some of us like a little discrimination. The Etrac doesn't seem to hit on targets ID with enough consistency for allowing that. I was amazed at all the variance of your other coins tested too. Thanks for posting your finds. You spent a lot of time for sharing with all of us.

 

[Elton]

n/t

 

[LilloEsquilo]

I don't really pay too much attention to the numbers. From what I've seen they can vary quite a bit. I've dug Buffalo that read 15-15 and just today a V nickle that was 13-13 in the ground here. They of course varied a bit but in general those were the numbers. Anyway what I go by is depth - if it's deep, I dig it. Not too many pulltabs are deep that I've found around here; you may get a few but if it's deep, odds are decent you'll get an older nickle. And there are plenty of them left out there, no doubt left by people who didn't care to dig that "junk" lower-mid tone or yet another pulltab. I'll take em.