Breastplate: for High Priest: Worn by Aaron
Source: Nav
Exodus 29:5
Take the garments and clothe Aaron with the tunic, the robe of the ephod, the ephod itself, and the breastplate. Fasten the ephod on him with its woven waistband.
Leviticus 8:8
Then he put the breastpiece on him and placed the Urim and Thummim in the breastpiece.