The Lycurgus cup (probably from the 4th century) has long fascinated students of ancient history and scientists alike. https://en.wikipedia.org/wiki/Lycurgus_Cup   First, it is a cage or reticulated cup, with "an outer cage or shell of decoration that stands out from the body of the cup." "It has mostly been accepted that the cage cups were made by cutting and grinding a blank vessel of solid thick glass, a laborious technique at which the Greeks and Romans were very experie