I have 5 x 1 dinar's from Yugoslavia, 1990, KM 142, or appear to be. I have 2 that I are 'normal' with the reeded edge, but 5 are 'smooth'. They are slightly smaller in diameter, and are about .15g lighter than the ones with the reeded edge.
when I use my 10x magnifying lens, it kind of looks like they were hit with a grinder, but it is so evenly done no one did it by hand. I'm wondering if this is something known, a strange subset of the coins not documented in the world catalogs or I just got a bunch from someones shop class that they were messing with.
If really interested, I can provide pictures, but I expect to be told, they are aftermarket modifications.
Here are the pictures.