UV - ultra violet.
You could take it to some bright sunshine, to see if the UV in that makes the colour glow a very bright luminous green. A completely different colour to the original glass.
Don't fret about the just learning bit - we were all there once. Frequently, I still am.

Here's a pic of a piece of amber coloured glass which contains uranium, taken in sunshine to show the green uranium glow up, on one side.