The ancient Romans carved different patterns in each layer of a multilayered onyx and often used the stone for their seals, carving a design in negative relief to produce the raised print.

Onyx gem stones are easily recognizable for their shiny black color, but the stone is also known for its deep meaning and purported healing powers. The meanings and healing powers of Onyx stones are part of the legends of these gems, which date back to ancient Greece and Rome.