A cage cup (Ancient Greek: Λυκουργος Ποτήρι ), also vas diatretum, plural diatreta, or "reticulated cup" is a type of luxury Late Roman glass vessel, found from roughly the 4th century, and "the pinnacle of Roman achievements in glass-making". Diatreta consist of an inner beaker and an outer cage or shell of decoration that stands out from the body of the cup, to which it is attached by short stems or shanks. About fifty cups or, more often, fragments have survived, and there are only a few in near-complete condition. Most have a cage with circular geometrical patterns, often with an "inscription", or phrase in letters above the reticulated area as well. Some have a flange, or zone of projecting open-cut moulding, above the lower patterns and below the lettering (only illustrated here by