Onyx
An onyx is a type of black rock mineral with white banded lines around it.
Onyx Media
The Gemma Augustea is a Roman cameo produced 9–12 AD and carved in a two-layered onyx gem (19 × 23 cm)
An onyx is a type of black rock mineral with white banded lines around it.
The Gemma Augustea is a Roman cameo produced 9–12 AD and carved in a two-layered onyx gem (19 × 23 cm)