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mclien
Inscrit le : 20 juil 2017
Messages : 4
Posté le : 20 juil 2017, 11h03
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Posté le : 20 juil 2017, 11h03
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Hi,
I need to find out the components of the alloy of a specific coin:
https://en.numista.com/catalogue/pieces1705.html
I read a bit about Aluminium-bronze and there are several which contain nickel. And since I want to make a jewellery piece from that, I'd like to find out, if it is nickelfree or not.
Any idea how to get that information?
cobra
Inscrit le : 21 juil 2007
Messages : 1053
Posté le : 20 juil 2017, 20h52
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Posté le : 20 juil 2017, 20h52
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Hello.
Aluminum + copper + tin.
No nickel.
Michel
mclien
Inscrit le : 20 juil 2017
Messages : 4
Posté le : 21 juil 2017, 12h39
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Posté le : 21 juil 2017, 12h39
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Hi Michel,
thanks for that. Any hint where to find those informations?
thanks
mclien
Mr. Midnight
Référent
Inscrit le : 10 mars 2017
Messages : 4001
Posté le : 22 juil 2017, 18h58
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Posté le : 22 juil 2017, 18h58
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I found this interesting paper on the subject.
http://www.biblical-data.org/MY_aluminum_Bronze.pdf
It is possible that it may contain up to 1% Nickel.
Jamais l'or n'a perdu la plus petite occasion de se montrer stupide. -Balzac
mclien
Inscrit le : 20 juil 2017
Messages : 4
Posté le : 22 juil 2017, 19h28
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Posté le : 22 juil 2017, 19h28
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Thanks for that. Interesting is the part, that it is actually mentioned, that this all is used for jewelry. Since the allergic problems with nickel...
Mr. Midnight
Référent
Inscrit le : 10 mars 2017
Messages : 4001
Posté le : 23 juil 2017, 13h41
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Posté le : 23 juil 2017, 13h41
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The alloys in the table are modern standard specifications for industrial uses. It does not tell us yet exactly what the Paris mint was using in the 1950s. (Your Moroccan coin was indeed minted in Paris)
It is interesting that the "Bronzital" CuAl6Ni2, which indeed was used in Italian coins of the 1930-1950s, is also found in more recent coins of Canada and India.
Also, I believe, but cannot prove that the alloy used in the nouveau franc centime coins after 1962 containing tin (Sn), cited by Cobra was different from that used up to to 1958.
Jamais l'or n'a perdu la plus petite occasion de se montrer stupide. -Balzac
MonaSeaclaid
Inscrit le : 21 jan 2016
Messages : 1007
Posté le : 7 août 2017, 3h25
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Posté le : 7 août 2017, 3h25
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Bronze is very typically considered a nickel-free metal and is generally safe for those with allergies to nickel. My understanding is that these days a bronze won't contain anything but the copper and tin.
http://www.naturallynickelfree.com/NaturallyNickelFree-handmade_jewelry_for_sensitive_skin/Metals_Info.html
There's a shortlist of safe metals.
You'll also want to check out the laws for the country you're in. For jewelry findings in a lot of places they're allowed to call it nickel free up to a certain amount. In the US they're allowed to say Nickel-Free up to 5%.
yvon
Inscrit le : 9 juin 2017
Messages : 1553
Posté le : 7 août 2017, 22h04
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Posté le : 7 août 2017, 22h04
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Hello,
What I usually do when I want to know the exact metal composition from a coin, I go to one of the big scrap-dealers/metal-traders they have nowadays this very accurate metal analyzer devices, who will give you the exact percentage (in tenths of a percent...)
You should look for the modern device what will check your coin in seconds, on a non-destructive way...
The good ones are even able to print it .
I like to have one, but the price is a problem (starting from 9.000,- euro...)
I hope this information was useful.
...you can run, but you can't hide...
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