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 Replies: 15 / Views: 6,815 |
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Pillar of the Community
United States
5207 Posts |
I found this Jefferson nickle the other day roll hunting. The reverse appears to have been "melted" however the coin is not warped or pitted like I would have expected if it had been torched. However the dark color and the slightly "raised" edge to the possible melt area on the right side of Monticello make me think that maybe it was torched. Any ideas?    |
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Pillar of the Community
United States
4809 Posts |
Hi Jack - can you get a more focused shot or two? This kind of looks like a nickel carloscoria found a few months back.
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Pillar of the Community
United States
1137 Posts |
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Pillar of the Community
United States
4212 Posts |
I've seen them similar, as the result of an arc welder.
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Bedrock of the Community
United States
62064 Posts |
The reason I feel it is PSD is that the blackened color is missing on the affected area. If that happened at the mint the patina would still be present on the affected area? So I feel it happened after it left the mint. |
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Pillar of the Community
United States
4809 Posts |
What if a piece fell off?
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Bedrock of the Community
United States
62064 Posts |
If the piece just fell off, then why are the edges near that area are raised? Even the Monticello is raised in the center of the design. The metal is pushed around probably by heat.
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Pillar of the Community
United States
1137 Posts |
Look at some examples of delamination and you will see a big difference between this coin and those and then you may understand why this is not a planchet flaw.
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Forum Kid
Canada
1074 Posts |
Defiently not an arc welder... maybe a small #1 welding tip using very little gas but not an arc welder... The whole coin would melt not just a little section. Metals characteristics are not like wax or plastics.
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Moderator
 United States
23522 Posts |
And nickel is among the hardest, and hardest to weld, metals. That's about 100 amps and a fairly big stick. A spark struck on nickel probably won't actually weld.
Edit to add: heck, a good hand could probably do that with a wire welder.
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Pillar of the Community
United States
1132 Posts |
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Forum Kid
Canada
1074 Posts |
Ok you guys a mig welder (GMAW) has a copper coated steel core wire usually a 0.35 diameter all it would do especially if it is flux core would strike and accumulate on top of the specimen. However it would not disappear in midst of nothing and leave a melted puddle. In addition Nickel has a melting point of 1455 degrees c. Steel has a melting point of 1425 to 1550 degrees c. When welding/heat treating nickel you don't weld it with a simple stick welder you would use a Tig welder or a Oxy fuel gas outfit. When welding nickel (Ni) you also need to insure that you are using a correct shielding gas because the oxygen reacts and causes a viscous scum to appear. Increasing the welding current will not increase penetration. Not to mention a Soldering device can reach up to 180 degrees c. and would not even mark the stock.
Although considering all of these points, it does contains copper and traces of other impurities so it will posses a lower melting point. My verdict either a genuine mint error or a oxyfuel torch outfit. If it helps I can experiment and tell you all my finds.
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Moderator
United States
23522 Posts |
Please do. I'd like to see you duplicate an arc pit (you can even see where the electrode struck) with a gas rig. I learned to weld 40 years ago, and I can't do it.
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Valued Member
United States
324 Posts |
I don't see any damage to the obverse so that pretty much eliminates punching or gouging on the reverse. I don't see any heat damage anywhere in the void so I doubt welding equipment of any type was used. Without better pictures, I am leaning towards a struck through scrap error.
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Moderator
United States
23522 Posts |
It could as easily have been an accidental arc as a deliberate act with a stick. Either way, you can see the initial contact point just below Monticello and the slight ridge outline from molten metal splashing away from the arc (which doesn't happen with gas - gas-melted metal obeys gravity).
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Pillar of the Community
United States
3507 Posts |
its damage of some kind. there is raised metal bordering the "gouge". That indicates damage after the coin was struck.
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Replies: 15 / Views: 6,815 |
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Posted 01/01/2015 8:10 pm
