Mystery Of The War Nickel

[BigSkyGuy]

Thanks GB. The winters are long and cold in Montana, so I have to keep myself busy!

[schoolofhardNox]

All fantastic posts and observations. So.....is it a leaching issue or is it an out of spec issue or is there something in addition to those, like our machines are so much more capable of analyzing the coins, or all of the above? Could there even be some sort of anomaly in new technology that has more than the usual problems with mixed metal identification? Kind of the way nails false high and hit in many non ferrous numbers? Are we getting a true ID or is some of it skewed by the processing of the signal? Kind of like harmonics when dealing with frequencies. So far the manganese factor seems to be the most probable to have something to do with it. Most of our silver coins  read pretty reliable, only changing due too wear. Our Cu/Ni coinage usually reads solid, but when you add manganese into the mix, you get what we have now. I wish I still had my DFX. I would love to see what they read on older technology.

[GB_Amateur]

9 minutes ago, schoolofhardNox said:

All fantastic posts and observations. So.....is it a leaching issue or is it an out of spec issue or is there something in addition to those, like our machines are so much more capable of analyzing the coins, or all of the above?

Maybe "all of the above" and then some.  We like to think of metal detectors as simple devices (well, some of us do...) but the hobby versions were made to find metals in the ground first and foremost.  We talk about 'conductivity' but although related to its scientific meaning, large(r) objects of poor innate conductivity can read quite high VDI's and vice versa for tiny, highly conductive metals (e.g. silver micro-jewelry).

It's a bonus that we can deduce properties using these otherwise utilitarian devices.  There's a lot of info in those signals as the most experienced detectorists learned with many hours of familiarity.  There's probably way more subtle info than anyone will ever have the time (or interest) to figure out.

[BigSkyGuy]

On 2/18/2024 at 6:04 PM, schoolofhardNox said:

is it a leaching issue or is it an out of spec issue or is there something in addition to those, like our machines are so much more capable of analyzing the coins, or all of the above?

Based on my tests it appears to be a leaching issue. I tested over 2,000 non-dug war nickels and only found three out of spec. @JCR has found several War Nickels that read high, but I suspect that he has not recovered thousands of them that read in spec. Also of interest, is that one of the three out of spec coins that I identified read low. I have not heard of anyone finding one the reads low. As GB mentioned the manganese was added to decrease the overall conductivity of the coin so that it matched the standard 75% copper/25% nickel coin.  Under mildly oxidizing conditions, manganese metal oxidizes to a very soluble ion (Mn+2), unlike copper which forms a relatively insoluble oxide coating on the metal. Therefore, the manganese leaches from the coin, increasing the conductivity.

[schoolofhardNox]

1 hour ago, BigSkyGuy said:

Based on my tests it appears to be a leaching issue. I tested over 2,000 non-dug war nickels and only found three out of spec. @JCR has found several War Nickels that read high, but I suspect that he has not recovered thousands of them that read in spec. Also of interest, is that one of the three out of spec coins that I identified read low. I have not heard of anyone finding one the reads low. As GB mentioned the manganese was added to decrease the overall conductivity of the coin so that it matched the standard 75% copper/25% nickel coin.  Under mildly oxidizing conditions, manganese metal oxidizes to a very soluble ion (Mn+2), unlike copper which forms a relatively insoluble oxide coating on the metal. Therefore, the manganese leaches from the coin, increasing the conductivity.

I agree with you and GB, that the manganese has to be the culprit. We can account for the higher readings but the low one must mean that copper or silver was leached out without the manganese loosing much. I guess under the right conditions, you could find a chemical way to do just the copper or silver. But it must be rare, since I didn't get many that read low.

[BigSkyGuy]

34 minutes ago, schoolofhardNox said:

We can account for the higher readings but the low one must mean that copper or silver was leached out without the manganese loosing much.

The low one was due to too much manganese being added at the mint.

[LawrencetheMDer]

Here are Manticore VID/VDIs for nickels (Beach low conductors) found MDing:

For gold as well as lead and foil, VIDs change with size and weight.  As weight increases so does VID. 

One variable to consider in the VID/VDI readings is the texture of the surface.  Gotta go for now.

Happy Hunting

[GB_Amateur]

On 2/20/2024 at 6:49 PM, BigSkyGuy said:

Under mildly oxidizing conditions, manganese metal oxidizes to a very soluble ion (Mn+2), unlike copper which forms a relatively insoluble oxide coating on the metal.

I see a minimum of three relevant environments for this discussion, and that is quite likely already an oversimplification:  1) saltwater, 2) acidic soil, 3) basic soil.  I've talked to some agricultural experts regarding the latter two and both can be found here in the greater Midwest, naturally, but basic dominates.  I emphasize 'naturally' because fertilizers are often used to changed the pH (i.e. the acidity vs. basicity) so what you get in the cultivated field could be different than surrounding non-cultivated land.  I don't know which side of neutral pH the rest of the country's soils represent.

A few years ago I reported on a mysterious copper coin I found which turned out to be simply the pure copper core of a USA clad quarter -- the 25%Ni, 75% Cu outer layers had been completely removed.  This coin was found in a decorative pond that was absolutely loaded with rotting leaves.  I assume the acidity was quite high (relatively speaking, not at a dangerous-to-human flesh level) in the pond, enough to eat away all of the two out layers.  Note that these outer layers are not simply a coating, but rather together make up 1/3 of the coin's weight (and thickness) compared to the 2/3 copper core.

What I'm getting at is that the chemistry and eventually the VDI anomalies for Warnicks may be due to different processes depending upon the particular environment the coin has been subject to.  (And there's still the wild card that in some apparently rare cases the composition tolerances were off at the mint.)

[JCR]

On 2/18/2024 at 5:17 PM, JCR said:

I got the time to re run my War Nickels in a more organized fashion. I only have 6, which is a very small sample compared to @GB_Amateur. I don’t have a MInelab, I used the Rutus Versa since that is what I am concentrating on currently. Park  Multi F Low conductors,  DD 23 coil.

1942S = 69

1943S = 54

1944S = 36

1944D = 35

1944P = 39

1945P = 38

 All with comparable wear.

A regular 1984 Jefferson = 33.

A new Zinc Cent = 58.

 From my small sample it seems the early war issue alloy may have been adjusted over time as war demands became more focused.  Frustrating for our purposes, but interesting.

I dug another War Nickel yesterday, 1943S. It comes in a bit lower at 51 than my other example but still shows my small sample trend of early war year production having higher TIDs.   Found in low wet ground, no major corrosion but encrusted with the minerals from the ground water like all items dug there.

[RSmith]

It may be that you have found some Henning nickels. Those counterfeit nickels could be producing a higher ID than a normal nickel.