1988 2 Deutsch Mark Kurt Schumacher

8 posts • 139回閲覧
GarySchmitz
Joined: 23 6月 2013
Posts: 11
Posted: 9 9月 2021, 17:53 #
Posted: #
This coin is shown to be “copper nickel clad nickel”, but it sticks to a magnet.

Why?
rsirian1
Joined: 20 11月 2020
Posts: 12959
Posted: 9 9月 2021, 18:02 #
Posted: #
Because nickel is highly magnetic.
Topic moved to "Numismatic questions" (ZacUK, 9 9月 2021, 18:35)
Idolenz Catalogue referee
Joined: 13 7月 2013
Posts: 9583
Posted: 9 9月 2021, 18:46 #
Edited: 9 9月 2021, 18:47
Posted: #
Edited:
Indeed they are out of Magnimat, 7% by mass pure nickel core with a Cu-Ni layers rolled onto on each side which is enough to make it attracted to a magnet.
GarySchmitz
Joined: 23 6月 2013
Posts: 11
Posted: 9 9月 2021, 22:00 #
Posted: #
引用する: "Then why don't nickles stick to magnets?"​Because nickel is highly magnetic.
​
BramVB Catalogue referee
Joined: 17 7月 2016
Posts: 2191
Posted: 9 9月 2021, 22:58 #
Posted: #
引用する: "GarySchmitz"​
引用する: "Then why don't nickles stick to magnets?"​Because nickel is highly magnetic.
​​
​Because they are made of copper-nickel (not nickel, as the nickname might suggest)
https://en.numista.com/catalogue/pieces44.html
Just call me Bram

No new swaps for the moment, still too many half-ongoing swaps to clean up!
GarySchmitz
Joined: 23 6月 2013
Posts: 11
Posted: 9 9月 2021, 23:02 #
Posted: #
引用する: "BramVB"​
引用する: "GarySchmitz So you're saying alloys of nickel aren't magnetic?"​
​
引用する: "Then why don't nickles stick to magnets?"​Because nickel is highly magnetic.
​​​
​​Because they are made of copper-nickel (not nickel, as the nickname might suggest)
​https://en.numista.com/catalogue/pieces44.html
​
rsirian1
Joined: 20 11月 2020
Posts: 12959
Posted: 10 9月 2021, 00:32 #
Posted: #
The nickel-copper alloys used for coins is 70% Cu / 30% Ni. It is non-magnetic and as you learned in one of your prior posts has a greyish color.
Idolenz Catalogue referee
Joined: 13 7月 2013
Posts: 9583
Posted: 10 9月 2021, 02:31 #
Edited: 10 9月 2021, 02:31
Posted: #
Edited:
If it where a homogenous Cu-Ni alloy you would need at least 56 percent nickel before the alloy shows any ferromagnetic properties at ordinary temperatures.
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