Silver Rounds?

An ASE is a monetized 1oz silver bullion coin backed by a government. Equivalent coins would be Canadian Maple Leaf, Mexican Libertad, Australian Kookaburra, etc. A silver round is merely the equivalent of a bar of silver and can be produced by a number of private entities. They will usually have a fineness and weight marked on the round and some can even be collected as medallic art. Rounds usually trade at or slightly below spot price, depending on the manufacturer.

Back in the late 60's early 70's bars were the most popular form of silver bullion and there were thousands of designs. In the early 70's the round form began becoming the preferred choice among coin collectors probably because of their coin-like shape. Once again there were MANY different private mints and many different designs. I knew a collector back then who had over ten thousand different rounds. With the advent of the silver bullion coins most collectors have been switching over to the legal tender coins and the rounds have become much less popular. There are fewer producers now and a smaller choice of designs. On the plus side though they can be had at often a much smaller premium over the spot price than the bullion coins, and there is no concern over what they grade.

I think most of them are fairly uniform in size, but there are always some that are off-size. Usually those off-size pieces aren't that popular because of their non-standardness.