Exodus 28:9-12

You shall take two onyx stones, and engrave on them the names of the sons of Israel, six of their names on the one stone, and the names of the remaining six on the other stone, in the order of their birth. As a jeweler engraves signets, so shall you engrave the two stones with the names of the sons of Israel. You shall enclose them in settings of gold filigree. And you shall set the two stones on the shoulder pieces of the ephod, as stones of remembrance for the sons of Israel. And Aaron shall bear their names before the LORD on his two shoulders for remembrance.