How can I determine what kind of metal it is?

[MadMike]

Hey gang,

so I got like 500 of some coin-sized plaques from a carpentry that went out of business a couple of years ago.
I don't know WHAT to do with them yet, I don't even know IF I'm gonna use them for something, but what I know is that I want to figure out what kind of metal they are made of - and I have no idea how to do so

What I can tell you is, they are not magnetic and the color can't be sanded away, so it's not a finish. I guess they are made out of brass or bronce or something similar, but is there any way to be REALLY sure about that?

Thank you in advance

 

[CSMacLaren]

Got pics?

 

[MadMike]

Sure, though I'm not sure if that really helps

 

[Mike J.]

A jeweller you are friendly with may be able to tell you what kind of metal they are. Failing that, you could try a scrap metal buyer or a pawn shop.

 

[cavx]

What is their weight?

Brass or bronze is normally heavier than a coin of the same size.

The Aussie 1 and 2 dollar coins are mainly aluminium with a very small percentage of copper mixed in to give them the gold colour. I was always told that copper would corrode aluminium, but apparently when bonded in a liquid state, they do don't react.

Maybe these are the same?

 

[jsher1010]

Some stainless steel isn't magnetic. Colour in the pic looks kind of dull silver/grey. Does it file easy?

 

[MadMike]

What is their weight?

I took some measurements today.They are 3cm in diameter, 2mm thick and weigh about 15 grams.

Colour in the pic looks kind of dull silver/grey. Does it file easy?

Well, I noticed that the pics arent the very best, so I took new ones, this time with some white background.
And...well, I dunno if they file easy, because idk how easy "easy" would be But filing is possible, to put it this way. Not the hardest material I've filed so far, but there have been softer ones as well

 

[Duncanator]

They look like brass to me. The bright yellow color is the same all the way through? Bronze is usually darker in color.

Brass is an alloy of copper and zinc. Bronze is an alloy of copper and tin with some other metals like aluminum, manganese and/or nickel.

What do you think you'll do with them?

 

[speedfreakz]

Looks like a brass token to me. Nice that the backs are blank. Should be soft enough to use a steel tool to scratch or cut them. Should also polish up nice.
You can lookup mints that make tokens for arcades or car washes. Might make interesting buttons or rivets

 

[Conqueror_Worm]

Based on the measurements you gave, the density is around 10.6 gm/cm^3, which is close to the density of silver.
The Scrapyard Handbook has a bunch of flowcharts for identifying metal:
http://biotech.law.lsu.edu/blaw/dodd/corres/pdf/416021h_0685/p416021h.pdf

 

[MadMike]

Based on the measurements you gave, the density is around 10.6 gm/cm^3, which is close to the density of silver.
The Scrapyard Handbook has a bunch of flowcharts for identifying metal:
http://biotech.law.lsu.edu/blaw/dodd/corres/pdf/416021h_0685/p416021h.pdf

I doubt that it's silver...although that would be great
Thanks for the link, I'll have a look later on.

They look like brass to me. The bright yellow color is the same all the way through? Bronze is usually darker in color.

Brass is an alloy of copper and zinc. Bronze is an alloy of copper and tin with some other metals like aluminum, manganese and/or nickel.

What do you think you'll do with them?

Looks like a brass token to me. Nice that the backs are blank. Should be soft enough to use a steel tool to scratch or cut them. Should also polish up nice.
You can lookup mints that make tokens for arcades or car washes. Might make interesting buttons or rivets

Yeah the more research I did the more it looks like brass to me as well, especially those two finishes on the front (matte and shiny) hint at that (at least for me).
I have actually no idea what to do with them (yet). Since I have so many of them (about 500), I always thought about replicating a small chest full of those Aztec coins from Pirates of the Carribean (not a very accurate, as the coins dont have the same size, and my coins would be stamped instead of embossed)...but I'm way too lazy to sand the front flat
Maybe I'll melt some of them down for some metal casting

 

[reididtenroc]

Look like commercial tokens ! Usualy this kind of items are made with cheap metal, like aluminium or white metal or aluminium aloy like "zamak".

 

[MadMike]

Look like commercial tokens !

As I said in my first post, they come from a carpentry that went out of business (that's why they still had so many). When I saw them for the first time, I thought they were some kind of business cards, but since there is neither a phone number nor an adress on them, that wouldnt make a whole lot of sense.

I THINK (or could imagine) that they glued these tokens in a corner of a customized cupboard or something you could order there, like a little maker's mark.

That being said, of course it could be some cheap metal, but as I said earlier, the golden color can't be sanded away, and zamak normally has a silverish-grey color

 

[reididtenroc]

Have you sanded very deep ? Because it's possible you have just saw the copper platting ?

It's also possible that is aluminium with a thermal treatment in this case sometime it become golden.