The "diamond" is a precious stone, the first in rank, value, hardness and lustre; the most perfect colour is the white. The "beryl" is a stone of a pale green colour, thought to be the diamond of the ancients: the word is "tarshish", and thought by some the "chrysolite".
The "onyx" resembles a man's nail, from whence it has its name: the word "shoham" here used is supposed to mean the "sardonyx", a compound of the "sardian" and "onyx" stones. The "jasper" is a stone of various colours and spots, variegated like a panther; hence the Targum here renders it "pantherin"; the most valuable is the green spotted with red or purple.
The "sapphire" is a stone of an azure colour or sky blue, exceeding hard and transparent. The "emerald" is of an exceeding fine green colour, very bright, and clear, and delightful to the eye; but is rather intended by the next word, as the "carbuncle" by this, which is a stone of the ruby kind, and very rare; see Isa 54:12.
"Gold" is mentioned along with them, and last of all, as being less valuable; but chiefly because these stones were set in gold, as the Targum paraphrases it; these are nine of the stones which were in the breastplate of the Jewish high priest , whom the king of Tyre might have knowledge of and imitate, as it is certain the pope of Rome does in some things:the workmanship of thy tabrets and of thy pipes was prepared in thee in the day that thou wast created; either born into the world; or made a crowned king; against which time, drums, and pipes, and such like instruments of music, were prepared in Tyre, and at them made use of by way of rejoicing: and as this was literally true of the king of Tyre at his coronation, so of the bishop of Rome at his creation and inauguration, which is attended with bells ringing, drums beating, trumpets sounding; and so in mystical Babylon is heard, though the time is coming when it will not be heard, the voice of harpers, musicians, pipers, and trumpeters, Re 18:22.
So R. Sol. Urbin. Ohel Moed, fol. 14. 2. Nat. Hist. l. 38. c. 8. Origin. l. 16. c. 7. Vid. Braunium de Vestitu Sacerdot. Heb. l. 2. c.