[convFixb]

I did the back-of-envelope calculation [and now you have to read it :)]:

A slug about 2 inches in diameter, 1/4 inch thick, is worth about 1 USD at today's copper price (weight = 1/4 pound).

So it might almost, but not quite, work as coinage. Maybe in a very poor country populated by body-builders.

[coffeebeqn]

Quarter pounder. Yeah maybe it would have to be some kind of a fractional currency. Or some more suitable metal. Silver would work but the price is a bit volatile. There already exists “bullion” silver coins that fit the bill