When a piece of glass is art, it does not have to be functional - it just is what it is.
I reckon the real problem is;
Is it
supposed to be roughly textured all over - satinated - produced by acid or sandblasting; a feature often found in glass, so would having it polished up (possibly an expensive proceedure) reveal something underneath - or ruin it forever.

Sometimes also, with modern art, you can't tell if it's something functional somebody has left in a corridor or an "installation".
(says she, who very gingerly stepped over an arrangement of mats which were colourful material fishies lying on the floor in a museum last week - and studying their (potential) artistic merit while doing so, only to come back later and find a load of schoolchildren lying on them to take their class! "Installations" don't
tend to do much for me.

)