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The word "magnetic" means different things to different people.
When playing with coins and magnets the following meaning is probably the most suitable.
"Magnetic coins" are real coins which can be picked up by a magnet.
- Magnetic coins are not themselves magnets:
- Magnetic coins do not normally stick to steel objects such as the panels of a refrigerator, paper clips or tacks
Whether a coin is "magnetic", "weakly or partly magnetic", or "non-magnetic", depends on the type of metal or metals from which the coin is made and the amounts of these metals in different parts of the coin.
Magnetic coins usually contain high amounts of magnetic steel or nickel throughout most of the coin.
Several old magnetic coins are made of pure nickel but because of the higher cost of the metal compared to steel, relatively few are in circulation today.
Most magnetic coins today are made mainly of magnetic soft steel or of magnetic stainless steel.
- Steel contains high amounts of iron together with other substances such as carbon, chromium, nickel and vanadium. How easy a particular steel rusts (corrodes) and how magnetic it is depends on what it contains and how it was made.
- Stainless steels do not corrode easily. Some stainless steels are magnetic, other stainless steels are non-magnetic.
- Simple carbon steel (soft steel) is magnetic but unless protected rusts easily.
- To reduce corrosion and for appearance, magnetic soft steel coins are usually covered with a layer of copper, nickel, cupro-nickel, bronze, or zinc. However this is so thin that it does not affect the magnetic nature of the coin as a whole
Magnetic coins which behave as if they are only "weakly magnetic or partly magnetic " are usually those that are only partly made from magnetic steel or nickel. High amounts of other metals are also present in such a way that the magnet cannot always get sufficiently close to sufficient magnetic metal to enable the coin to be picked up easily.
Those coins which cannot be picked up by a magnet, "non-magnetic coins" are those made mainly of non-magnetic metals such as aluminium, copper, gold, silver or zinc.
Sometimes "non-magnetic" coins may contain iron or nickel but in such an amount or form, that the magnet-attaching properties of the pure metal are not exhibited.
- The copper alloy "cupro-nickel" is widely used in coin production. It contains 25 percent nickel but is non-magnetic.
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For appearance, the surface of some non-magnetic coins may be covered with a layer of nickel so thin that it is insufficient to change the "non-magnetic" nature of the coin as a whole.
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Copper-plated steel UK 1 and 2p coins and Euro 1,2 and 5 cent coins are magnetic
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Nickel-plated steel UK 5p and 10p coins dated 2011 are also magnetic.
In "The Welsh Giant" the coins are standing vertically on two encased ceramic magnets (Magic Penny Magnets)
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1 and 2 Euro coins are only partly magnetic and will stick by their rims only to very strong mangets, like this levitating, very strong but potential dangerous, neodymium magnet.
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Old and new brass-plated steel Argentinan coins are also magnetic. In this rose/mandala they are balanced vertically on a ceramic manget reinforced by a neodymium magnet below.
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