They have been used and there is some slight staining in some commensurate with age.
These are in the satinato finish black on the outside and white inside and they are unmarked.
Carlo Moretti designed this range of drinking glasses in the early 1960s and they would have been produced at Murano in Venice Italy.
These wine glasses are approx 12.5cm tall (5") and hold 20cc. These are hand blown glasses so there is some slight variation in thickness of the glass.