I am sure they are either stainless or some form of alloy.
Since they won't be used for chopping trees, stainless or alloy makes more sense.

Rust and tarnish resistant would be much more reasonable and practical for this type of item / coin.

I am sure they are made by an outside company, not Dan or Jerry.

It wouldn't be worth their time or effort to purchase and set up tooling for a single or even a couple of runs of coins.

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