Zinovia
Explorer
I didn't find anything about this on a search of ENWorld so figured I had to post it. Apologies if it's old news.
From the Christies auction house:
A ROMAN GLASS GAMING DIE
PRICE REALIZED
$17,925
A ROMAN GLASS GAMING DIE
Circa 2nd Century A.D.
Deep blue-green in color, the large twenty-sided die incised with a distinct symbol on each of its faces
2 1/16 in. (5.2 cm.) wide
PRE-LOT TEXT
THE PROPERTY OF A
MARYLAND FINE ARTS PROFESSOR
PROVENANCE
Acquired by the current owner's father in Egypt in the 1920s.
LOT NOTES
Several polyhedra in various materials with similar symbols are known from the Roman period. Modern scholarship has not yet established the game for which these dice were used.
Also an article on wired.
From the Christies auction house:

A ROMAN GLASS GAMING DIE
PRICE REALIZED
$17,925
A ROMAN GLASS GAMING DIE
Circa 2nd Century A.D.
Deep blue-green in color, the large twenty-sided die incised with a distinct symbol on each of its faces
2 1/16 in. (5.2 cm.) wide
PRE-LOT TEXT
THE PROPERTY OF A
MARYLAND FINE ARTS PROFESSOR
PROVENANCE
Acquired by the current owner's father in Egypt in the 1920s.
LOT NOTES
Several polyhedra in various materials with similar symbols are known from the Roman period. Modern scholarship has not yet established the game for which these dice were used.
Also an article on wired.