The piece is called a sculpture. That's the official name for it.
And I can't iterate hard enough that Mdina is the factory name, if that is all that is on the base, it is MARKED.
As well as the Mdina mark, some pieces are signed by Joseph Said, some by Eric Dobson, very few are signed by Michael Harris, normally these have "Mdina Glass, Malta" after his name. Often the ones with Said's or Dobson's signatures have a date.
A named artist signature adds a premium to the value.
End of day is a lousy term - I know it's been in use for a long time, but it's a misnomer and should be obliterated from the language.
Most of the things described as such, are things like friggers - apprentice pieces, made to show off their skills - not things made at the end of the day to "use up" glass. I don't believe it's neccessary to "use up" glass at the end of the day - it's probably a term coined by somebody who didn't have a clue what they were talking about!