John Gill Bible Commentary

And the rulers brought onyx stones, and stones to be set,.... Or "stones of fillings" (d), to be set in ouches, and fill them up, as stones set in rings do: for the ephod, and for the breastplate; the onyx stones were for the shoulder pieces of the ephod; and the other stones were for the breastplate of judgment, and both to be borne by the high priest, for a memorial of the children of Israel before the Lord, whose names were engraven on these stones: the rulers are mentioned last, as bringing their offerings: the reason of which may not be, because they were backward to it, for they might offer earlier, though recorded last; or if they offered last, it might be because they brought things that others could not; namely, the precious stones here mentioned, and other things in the next verse, the common people had not; though some of the Jewish writers tax them with dilatoriness, and observe a letter wanting in the word for "rulers", it generally has; omitted to denote, as they think, that they were slow and backward in offering; so Jarchi notes from R. Nathan. (d) "lapides plenitudinum", Pagninus, Montanus; "repletionum", Vatablus; "impletionum", Drusius.