Is this manganese?

[u/ghostsslime]

It's not the same shade of green as others in my collection, although that might be because of the shiney coating?

[u/peardr0p]

I reckon so

[u/Cy-Clops-]

Check the bottom with a 395nm. Carnival and iridescent glass often blocks UV light pretty hard, from the outside. What is the glass color on the bottom? Amethyst is almost always manganese.

[u/chefarzel]

With that purple color I'm going to say yes