Title from resource description page.
Mode of access: internet.
Narrator, David Whitehouse, former curator, The Corning Museum of Glass.
Cage cups were made by Roman glasscutters in the fourth century A.D. The entire vessel was cut from a thick-walled glass hemisphere. The metal attachments show that the object was a hanging lamp. Imagine the shadows the "cage" would have cast as the lamplight flickered.
Not commercially distributed.