This is a sard gem engraved with a snail and a bird standing on its shell. This object dates from the Roman Imperial period (1st-3rd century) and is being kept in the Greek and Roman Antiquities Department of the British Museum .
The snail is sinistral, with some axial markings on the last whorl; the animal is stylised, with two tentacles.
 BML, inv. [GRA] 1814.0704.1439. http://bit.ly/1lGgk4n.