Assertion: image | /r/HasProperty | restricted to heretical groups of christians
Facets:
value: at this period
type: TEMPORAL
Source sentences:
text: Some engraved gems thought to be 2nd or 3rd century have survived, but the subject does not appear in the art of the Catacombs of Rome, and it is thought that at this period the image was restricted to heretical groups of Christians.