Quoted from LTG:

I might add I don't know the percentage, but they are real silver.
LTG : )

Quoted from LTG:

When the game shipped, it came with a box of 300 tokens. And supposed to be around 6 silver ones included to try and entice players to keep playing and trying to win the silver ones.
Early boxes of 300 when you bought them separately should have some too.
I had the first one from my distributor for test. I opened the factory sealed carton and plastic sleeves of tokens myself, to install in the machine. I didn't have any silver ones included in my set. Williams inquired how my players reacted to the silver ones. I told them there weren't any with my game. I was told there were. I mentioned that I collected coins most of my life and know the difference between brass and silver, and the tubes in the game where they were in are clear lexan, so you could see that all of mine were brass.
I never heard any more about them. No idea if someone at the factory was removing them or what.
So no way of knowing how many are really out there and could be rare like the prototype bronze tokens.
LTG : )

Quoted from LTG:

There was a time before they were remade that you could get $2 or $3 apiece on Ebay. for the brass ones.
LTG : )

Quoted from LTG:

Yes. I don't know the quantity, I'm sure it's not a lot. They are worth something.

There are two different sizes. One for America and a slightly different one for Europe. Otherwise they should work, brass or silver. Unless the different size is the issue.
LTG : )

Quoted from LTG:

Weird that yours are all the same design. They came in every design, 27 different ones I think.
I wonder if yours aren't original, but ones that someone made ? That would explain why they don't work in your magic token coin chute.
They should ring like a silver coin when dropped on a table, if silver.
LTG : )