Exodus 39:28-31

28They made the turban and the ornate headbands of fine linen, the linen undergarments of finely spun linen,

29and the sash of finely spun linen expertly embroidered with blue, purple, and scarlet yarn. They did just as the Lord had commanded Moses.

30They made a medallion, the holy diadem, out of pure gold and wrote on it an inscription like the engraving on a seal: Holy to the Lord.

31They attached a cord of blue yarn to it in order to mount it on the turban, just as the Lord had commanded Moses.