Found a plated 56-D Lincoln-----

GaCoinGuy

Now here's my question....

What sort of plating would be magnetic? Is chrome magnetic?

keyman64

Chrome/Chromium itself is not magnetic (at room temp). Generally, things that are chrome plated have a magnetic substrate and are of course magnetic because of that.
Clear anodized aluminum can imitate the look of chrome plate very well but again is not magnetic.

Chromium is remarkable for its magnetic properties: it is the only elemental solid which shows antiferromagnetic (non magnetic) ordering at room temperature (and below). Above 38 °C, it transforms into a paramagnetic (attracted to a magnet) state.

ricko

Is it plated or counterfeit?? Cheers, RickO

keyman64

<< <i>Is it plated or counterfeit?? Cheers, RickO >>

Without seeing it and if it is magnetic then I would guess steel counterfeit but a weight of it could maybe lead to a foreign planchet...if there were countries using steel for coinage that the U.S. Mint was helping that year...a bit of a stretch I think.

silverpop

120% sure it's plated

just someone was bored and plated a coin for fun

seen many of these

MsMorrisine

steel is obviously magnetic, as are cobalt and nickel

BillJones

What about mercury? Quite often kids woudl dip coins in mercury in the old days to make them look shiny. This was before it was generally known that mercury is a cumulative poison that can be absorged through the skin.

ms70

<< <i>steel is obviously magnetic, as are cobalt and nickel >>


Nickel is magnetic?

keyman64

<< <i>

<< <i>steel is obviously magnetic, as are cobalt and nickel >>


Nickel is magnetic? >>

Don't forget about lodestone, gadolinium, neodymium and samarium.


Because Nickel (Ni) is ferromagnetic it is used in making Alnico magnets (consisting of aluminium, nickel, and cobalt).

Note that the U.S. five cent coin called a “Nickel” is made of 75% copper and 25% Nickel (Ni). Even though it contains Nickel (Ni), a ferromagnetic material, they aren’t visibly attracted to magnets.In fact, they don’t interact with magnets like many other non-magnetic materials.

What is interesting is that dimes and quarters will visibly interact with a STRONG moving magnet. This is odd because dimes are quarters are both about 92% Cu and 8% Ni – not too different than Nickel (the coin). It’s even been noted that Nickels are harder to find with metal detectors than other coins.

It may be that the Nickel (Ni) in the nickel coin somehow disrupts the electrical currents. This seems possible since adding Nickel (Ni) to Iron, Carbon, and Chromium a form of stainless steel is created that is not magnetic even though it contains Iron. But dimes and quarters have Nickel as well, just less.


So, just because something is scientifically magnetic, does not mean that if you wave a weak refrigerator magnet over the coin you will see something happen.

Cameonut

Nickel is magnetic. Not as strong as iron, but it will show magnetic properties.

I used to work in one of the largest plating factories in the US. I know of no other commonly plated material that has magnetic properties to be attracted to a magnet. (other than perhaps more recent nickel-iron alloys)

Not chrome, not copper, not zinc, not silver, not gold.

291fifth

<< <i>What about mercury? Quite often kids woudl dip coins in mercury in the old days to make them look shiny. This was before it was generally known that mercury is a cumulative poison that can be absorged through the skin. >>



This used to be quite common in high school chemistry classes back in the 1960's. It was strictly fooling around and no one really considered just how toxic such coins were.

CaptHenway

I have heard that some chrome platings are magnetic, but I do not know the chemistry. I do know that if you place some plated coins on a glass tabletop and place a magnet next to it you can slowly drag the coins sideways by moving the magnet.

As to why, the guy I used to work for at Collectors Clearinghouse once told me that he knew a guy who worked at a plant that replated chrome car bumpers. (You oldtimers will remember those.) He said that the guy said that whenever he mixed up a batch of plating solution he would test it by taking a coin out of his pocket and plating it. Afterwards he just spent the coin.

GrumpyEd

I think it's because when they chrome plated it, they first plate with copper then nickel and the nickel layer makes it magnetic.

The nickel layers in clad coins don't make them magnetic enough to pick up with magnets but the plated on layers do, you'd need to ask a metal guru why it works that way.

https://en.wikipedia.org/wiki/Chrome_plating

Cameonut

<< <i>I think it's because when they chrome plated it, they first plate with copper then nickel and the nickel layer makes it magnetic.

The nickel layers in clad coins don't make them magnetic enough to pick up with magnets but the plated on layers do, you'd need to ask a metal guru why it works that way.

https://en.wikipedia.org/wiki/Chrome_plating >>



Exactly right Ed.

With a traditional copper-nickel-chrome coating, the process is almost always to start with plating a thin coating of copper on the piece. Copper plating has the ability to deposit deep into recesses compared to some other metals. The copper layer tended to be 0.0002" or less and is a great "primer" coating. The real corrosion resistance of chrome parts comes from the nickel layer applied on top of the copper. Depending on specification (think of it as interior vs exterior for auto parts), the nickel layer was about 0.0002" to 0.0005". Most people when looking at bright nickel plating would easily mistake it for chrome, but it always has a yellowish tint to it. To get the bright white chrome finish, the chrome was applied over the nickel layer. Hence the name copper-nickel-chrome for this type of work. Decorative chrome finishes are porous to oxygen and salt and extremely thin - so not corrosion resistant. Think chrome thicknesses of millionths of an inch - so thin that we didn't have a good means to measure it's thickness (at least at the time). So the corrosion resistance of the part was determined by the thickness of the nickel layer under the chrome, not the chrome itself. This description is more for plating on typical steel parts - zinc die castings are a different matter, but very similar.

I also have some experience with what is known as "hard chrome". It is possible to plate much heavier coatings of chrome on pieces than the "millionths of an inch" seen on decorative pieces. The purpose of hard chrome was to take advantage of chromes ability to resist wear in industrial applications. It is extremely hard and wear resistant. In our case, we had several sets of hard chrome tanks set up to plate a variety of machine parts. For example, we had machine shafts that tended to wear out over time in production. Instead of buying a new shaft ($$$$) or making one ($$$$) we would simply plate hard chrome on it to build up the shaft to specification. No copper or nickel layers - just chrome. We could plate on shafts as long as 8 feet and a foot in diameter. This process took a long time to build up thousandths of an inch of chrome and was as much an art as science - some jobs took a week to finish. Alas, I suspect this art has died out in the US as manufacturing has fled the country.

So there you have it, more info on chrome plating than you would ever want to know.

I suspect the original piece has a heavy coating of nickel on it.

Also, there was some commentary on mercury. Mercury is higher on the electromotive series when compared to copper (+0.85 volts for Mercury vs +0.34 volts for Copper). This means that if you put a copper piece in contact with mercury (or mercury solutions), the mercury will preferentially deposit a coating on the copper. This is normally called "immersion plating". Many of us did this as kids before the government decided that mercury was so dangerous that we could no longer do that type of "fun" stuff.