“You are to make a breastpiece for use in making decisions, ¹  the work of an artistic designer; you are to make it in the same fashion as the ephod; you are to make it of gold, blue, purple, scarlet, and fine twisted linen.

He made the breastpiece, the work of an artistic designer, in the same fashion as the ephod, of gold, blue, purple, and scarlet, and fine twisted linen.