I doubt it's true, but don't quote me- I have no "real" proof. I was just there this weekend and experienced -strong- evidence to support otherwise. Also, normally these things make some kind of news. I will say one thing though - someone has either been copying the method or the mintman decided to make a really poor quality batch.
I say this while I stare at a pile of Pink A's and 4 green dots. Two of the greens are very "mintlike" per the pics I've seen and the other two are much more crude looking, although the same color. When I say crude, I mean, they look like rough, off round copies.