1955 Silver (Steel) Penny?!?

I've got one like this ( a 1944 LWC) in my stash somewhere....from about 30 years ago...and a dealer back then told me it was mercury.

Actually, if I may, hold the phone a minute there. I too have recently come across a coin demonstrating this same sort of defect, and I can say with reasonable certainty that what you have there is neither plated nor in a bezel. And interestingly enough, nor is it silver.

Since coming across this particular coin, I have begun scouring the forums for similar specimens. I have come across four so far, with mine bringing the total to 5. (Mine is from '56.)

The following details should be noted about this and other similar coins before an accurate conclusion can be drawn:
First, these coins are Cu/Ni, not silver or Cu/Zn. Or at least mine is. Luster and hue are consistent with modern nickels but not with other silver coins I own from that time period. Due to the raised edges that envelop most of the coin's wear points, these coins are likely to exhibit very little wear, even after several decades. The resulting luster is quite easily mistaken for silver, as Cu/Ni purports to mimic many of silver's observable qualities. Furthermore, a simple ring test will demonstrate that when struck on marble, the coin exhibits a dull thud like that of a nickel rather than the deep, bell-like resonance of silver coinage.

Secondly, the ring surrounding the edge of the coin is not attached to the coin at the inner lip. Rather, the metal surrounding the face the coin is curled inward. Below I have included a (crude) diagram of what the cross-section of the coin would look like if one were able to look more closely. This seems to contradict the bezel theory, as said bezel would not be well-designed if it were to adehere only to the outermost edge of the coin, allowing dirt and corrosives to become trapped around the coin's inner edge.

Thirdly, and perhaps most supportive of the off-metal strike argument, all 5 coins have something else in common: the presence of a tool mark. Each of these coins exhibits some sort of prying damage to the rim. It is generally visible primarily from the tails side, and is always located slightly off-center at the bottom of the rim, i.e. between the two wheat stems or directly above Lincoln's head if you turn the coin over. This would seem to suggest the possibility that there had been a ring or clasp that had been pried or had fallen off. However, if such were the case, some jagged edge or weld/solder mark would likely still remain, and this does not appear to be the case in any incidence. In fact, the "ring" around the coin bears no indications of metal work whatsoever, such as seams or soldering points.

And finally, perhaps significanly, perhaps not, all of the coins appear to have been minted between the years of 1955 and 1960, supporting the theory of a possible flaw in the one-cent dies from around that time. With all of this said, here's my theory:
I believe these coins to be off-metal strikes produced when a nickel planchet made its way into a penny die. Due to the size difference between said coinage, the die strike caused displacement of the excess metal, which, when pressed against the retaining collar, had nowhere to go but to "ooze" out from the edges of the rim and around the dies. When the dies separated, one side was pulled quickly away, causing the surrounding edge to curl inward (think gift ribbon being dragged along the blade of a scissor to create curls). Meanwhile, the opposing face remained firmly affixed to the die, such that it had to be pried away manually, causing the tool mark.

While certainly not as valuable as silver dime-planchet pennies, it is likely that errors of this type are somewhat more rare, as any coin that had to be removed from the machinery by hand should have gone straight back into the furnace before ever leaving the mint, whereas a silver penny would have fallen right in with all the rest. There's a good chance what you have is a $500+ item. I really do hope you still have it, as unless I miss my guess, a real expert, able to observe the coin in person, should be able to authenticate that what you have is a highly rare mint error.

So, what you're saying is that someone plated this coin at some point after a metal gouge was dug into it? The close-ups clearly show that this coin is Cu/Ni through and through. And why plate in Cu/Ni?

Furthermore, I am suggesting the possibility that some aspect of the dies during a brief period of ~6 years allowed it to occasionally take in an oversize planchet. It's not that much of a stretch.

I do believe this to be a form of broadstruck error. I think the collar cut out a penny-sized chunk of the planchet, which then gummed up the works. That's what it looks like to me.

Other than what was already posted about this coin
i was wondering if the mint was doing any foreign coins
that year. I also did not see a weight on this coin.

Bronze coins, when rubbed with mercury, turn silvery in appearance.
However, after some months or years, the coin will start to darken.
This because there is transmigration of the mercury and copper into each other, and a more homogenius and thicker amalgam is formed on the surface of the coin.

Perhaps biochemist6 may add further comment to this.

Silver or other white metal plating is more likely, if the silvery appearance has been retained for a number of years.

My guess is it was electroplated by a schoolkid doing a basic science experiment. It's a pretty common experiment, too.

Well I guess we can make that 6 Penny's like this now .....I too have a 1955 silver/steel?penny I've searched all over the internet for the last year or two and finally I found some info here has anyone officially determined the exact value yet?

I hope some of you are still following this...
I have two Lincoln chrome colored coins:

1958 Lincoln Wheat cent - the chrome color is somewhat dull; there are to scratches on obeverse side to the left of his face, like someone was trying to scratch coating off, but it is still chrome color underneath; it also has nicks around the rim, like someone used a pen knife to try and see under the chrome; and it is NOT magnetic.

1978 Lincoln Memorial cent - again it is chrome color, but shiny as opposed to dull; no nicks or scratches; and it IS magnetic.