You shall make settings of gold filigree,
Directions are here given concerning the ephod, which was the outmost garment of the high priest. Linen ephods were worn by the inferior priests, Sa1 22:18. Samuel wore one when he was a child (Sa1 2:18), and David when he danced before the ark (Sa2 6:14); but this which the high priest only wore was called a golden ephod, because there was a great deal of gold woven into it.
Commenting on Exodus 28:6-14
And thou shalt make ouches of gold. Or sockets of gold, to put the two onyx stones in, Exo 28:11 for of other ouches we read not, excepting the enclosings, in which the twelve stones of the breastplate were set, Exo 28:20 and these are again mentioned because of the chains to be fastened to them, of which in the following verse.
Ouches of gold - משבצת mishbetsoth, strait places, sockets to insert the stones in, from שבץ shabats, to close, enclose, straiten. Socket, in this place, would be a more proper translation, as ouch cannot be traced up to any legitimate authority. It appears sometimes to signify a hook, or some mode of attaching things together.