'Diadem' in the Bible

Then I said, "Let them place a pure diadem on his head." So they placed the pure diadem on his head and clothed him with fine garments while the angel of the LORD was standing beside them.

And Yahweh their God will save them on that day, as the flock of his people; for [they are like] the stones of a diadem, glittering on his land.