Aluminium-bronze: Alloy components?

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Joined: 20-Jul-2017
Posts: 3
I need to find out the components of the alloy of a specific coin:
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?
Joined: 21-Jul-2007
Posts: 1045
Aluminum + copper + tin.
No nickel.
Joined: 20-Jul-2017
Posts: 3
Hi Michel,

thanks for that. Any hint where to find those informations?

Mr. Midnight
Joined: 10-Mar-2017
Posts: 131
I found this interesting paper on the subject.
It is possible that it may contain up to 1% Nickel.
Joined: 20-Jul-2017
Posts: 3
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
Joined: 10-Mar-2017
Posts: 131
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.
Joined: 21-Jan-2016
Posts: 930
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.

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%.
Joined: 9-Jun-2017
Posts: 121

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. can run,  but you can't hide...

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