1921S Walking Liberty Half Medal

A friend of mine has a coin, that looks almost identical to a walking liberty Half Dollar, but 2 things stick out about it right away. The first is that it is slightly smaller than a regular half dollar, (this is how he identified it) and I think it is only about 1-1.5mm smaller.

The second thing which I noticed is, it has a medal orientation. So I'm pretty sure this isn't a regular US circulating issue or even an error coin, but I don't know what it actually is. A special minting for collectors? A sample by a manufacturer? Toy currency?

At first guess, I'd say it was silver, but it was in a cardboard holder and I didn't take it out to try and verify that.

Hello,

It's quite hard to say for sure without any photos of this medal.

But from what you said it could just be a regular US half with a rotation/alignment error that someone forgot about, maybe it was once fitted as part of a piece of jewellery?

a 180 degree die rotation error on an undersized planchet? seems unlikely to be an error to me. i can try to get a picture of it but it looks just like a walking liberty half to me other than the irregularities I've mentioned