Vintage Blown glass necklace

Hello I’ve just rediscovered this lovely glass necklace that I found many years ago, I was fascinated by it and couldn’t believe someone took the time to make it, and the amount of work that has gone into it, I’ve never ever found another the same, I guessed it was murano as has some kind of class about it, looks almost antique, and i think clasp was changed at some point, but other metal looks antique.