Gem
Object type: Gem
Department: Medieval Art
Culture: Roman
Date: 2nd–4th century
Medium: Nicolo (variety of onyx having bluish layer over black).
Dimensions: Overall: 1/2 x 3/16 in. (1.3 x 0.4 cm)
Classification: Lapidary Work-Nicolo
Credit line: Rogers Fund, 1922
Accession year: 1922