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 Replies: 11 / Views: 7,906 |
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Pillar of the Community
United States
1912 Posts |
I came across some small print in a KM catalog under Italy. For some certain stainless steel coins (KM76a/b & KM78a/b) there are magnetic and non-magnetic versions. I've always thought stainless steel was not magnetic. Before this, I never noticed this small note. And I have both versions. I mention this because it is common to see the subject of magnetic attraction when it comes to helping people identify coins. And in general, if a coin is or is not attracted to a magnet, it usually means one thing or another. In this case, what appears to be the same coin, can come in both flavors.
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Valued Member
United States
280 Posts |
The final years of Canadian Cents came both Mag & non. I have a RCM roll of nice gem BU magnetic 2012 final year Canadian cents. I also have a roll of US 1943 S Steel Lincoln cents. I have some UK new pennies that are magnetic & some Italian steel coins...& I have always loved magnets ! |
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Pillar of the Community
Canada
4227 Posts |
Here's a post I made somewhat recently pertaining to the 1939 Albania lek (minted in Rome) that's on this subject. I wonder what the ratio is for the Italian coins? https://goccf.com/t/260713 |
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Pillar of the Community
United States
6130 Posts |
Here's a neat article on the subject; I have a ton of those coins but never really thought to check if they were magnetic. http://www.scientificamerican.com/a...ets-work-on/Italy probably contracted to the lowest bidder for their metal and/or planchets, resulting in different types of stainless steel for different years. It apparently all comes down to the atomic structure of the metal to determine whether it is magnetic. |
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Pillar of the Community
 United States
1912 Posts |
What a great post and link. Interesting explanation.
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Valued Member
United States
136 Posts |
For the italian issues during WWII there are a few that are slighlty magnetic, non magnetic and magnetic,
There are a few different types of varieties out there
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Pillar of the Community
Australia
3831 Posts |
Some stainless steel can be magnetic - it depends on what alloy it is.
The same is with nickel - pure nickel is magnetic however as soon as it is alloyed, it no longer is magnetic. And then you have cobalt and rare earth metals but they are not used for coinage.
My partial coin collection http://www.omnicoin.com/collection/gxseriesMy numismatics articles and collection: http://www.gxseries.com/numis/numis_index.htmRegularly updated at least once a month. |
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Pillar of the Community
United States
937 Posts |
There are at least 450 types of stainless steel.
For most of us laymen we can separate them into three groups
Magnetic: these are the most common types used for things like inexpensive flatware, tables and work benches. They have high ferric content and are easiest to machine, weld, and form.
Non-magnetic: This has a low ferric content and is harder and more difficult to work with. Better grade flatware, pans, and utensils. The 18/8 'food grade' (18%chromium and 8% nickel) and medical grade falls in this range.
Space grade: Very to extremely low ferric content used mostly in space.
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Pillar of the Community
United States
1912 Posts |
Stainless steel must be a whole science in itself. My curiosity was peaked just because I happened to notice magnetic and non-magnetic coinage printed in the Krause catalog. I just don't recall seeing that in small print among some of the coins for different countries before. There is one part in one other reply I found most interesting. That is a coin may not be magnetic at all unless you might test it with a strong magnet. Then after that it may very well be a little magnetic. To that end, that might explain some observations I have among my own coins. Some of them are clearly not attracted to a magnet, while others certainly are. But then there are others that are ever so slightly reacting to a magnet
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Pillar of the Community
United States
6130 Posts |
 Magnets. How do they work? |
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Pillar of the Community
Russian Federation
5172 Posts |
I'm usually testing coins with a small neodymium sphere magnet straight out of a Neocube, which I suppose is a little stronger than your typical fridge magnet. I did occasionally get inconclusive results with the weaker fridge magnets, but thought that was because their magnetic power was generally not enough to move such a large and heavy object as a coin.
Are there any (reasonably cheap/common) coin types made of pure enough nickel to actually be magnetic? (I keep seeing mentions that there are some such types, but can't recall any specifically.)
If so, would be nice to see if they are actually attracted significantly less (than the normal steel coins, which easily jump out).
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Pillar of the Community
Canada
1747 Posts |
Canadian nickels from 81 and before are 99% nickel
Canadian dimes from 68 to 99 are 99% nickel (some 68's are silver copper)
Canadian Quarters from 68 to 99 are 99% nickel (some 68's are silver copper)
you should be able to find these in your local LCS or even banks for free to less than face value (in the USA)
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Replies: 11 / Views: 7,906 |
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Posted 06/27/2016 10:25 am
