The Tribes of Israel: Names of, Engraven on the Breastplate of the High Priest
Source: TTT
Exodus 28:21
The twelve stones are to correspond to the names of the sons of Israel, each engraved like a seal with the name of one of the twelve tribes.
Exodus 39:14
The twelve stones corresponded to the names of the sons of Israel. Each stone was engraved like a seal with the name of one of the twelve tribes.