Exodus 28:36-39

36And thou shalt make a thin plate of pure gold, and engrave on it, as the engravings of a seal, Holiness to Jehovah!

37And thou shalt put it on a lace of blue, and it shall be upon the turban — upon the front of the turban shall it be.

38And it shall be upon Aaron's forehead, and Aaron shall bear the iniquity of the holy things, which the children of Israel shall hallow in all gifts of their holy things; and it shall be continually on his forehead, that they may be accepted before Jehovah.

39And thou shalt weave the vest of byssus; and thou shalt make a turban of byssus; and thou shalt make a girdle of embroidery.