Settings - Ouches of "cloisonnec" work, like those mentioned in Exodus 28:11.
A sardius - i. e. "the red stone." The Sardian stone, or sard, was much used by the ancients for seals; and it is perhaps the stone of all others the best for engraving.
Topaz - Not the stone now called the topaz: it may have been the chrysolite, a stone of a greenish hue.
A carbuncle - More probably the beryl, which is a kind of emerald.

Four rows of stones - With a name on each stone, making in all the twelve names of the twelve tribes. And as these were disposed according to their birth, Exodus 28:10, we may suppose they stood in this order, the stones being placed also in the order in which they are produced, Exodus 28:17-20 : -
Four Rows of Stones First Row Sons of Leah Sardius or Ruby Reuben ראובן Topaz Simeon שמעון Carbuncle Levi לוי Second Row Emerald Judah יהודה Sapphire Issachar יששכר Diamond Zebulun זבולן Third Row Sons of Bilhah, Rachael's maid Ligure or Jacinth Daniel דן Agate Naphtali נפתלי Son of Zilpah, Leah's maid Amethyst Gad גד Fourth Row Beryl or Crysolite Asher אשר Sons of Rachel Onyx, or Sardonyx Joseph יוסף Jasper Benjamin בנימין
In this order the Jews in general agree to place them. See the Jerusalem Targum on this place, and the Targum upon Song 5:14; and see also Ainsworth. The Targum of Jonathan says, "These four rows were placed opposite to the four quarters of the world; but this could only be when laid down horizontally, for when it hung on the breast of the high priest it could have had no such position. As it is difficult to ascertain in every case what these precious stones were, it may be necessary to consider this subject more at large.
1. A Sardius, מדם ,su odem, from the root adam, he was ruddy; the ruby, a beautiful gem of a fine deep red color. The sardius, or sardie stones, is defined to be a precious stone of a blood-red color, the best of which come from Babylon.
2. A Topaz, פטדה pitdah, a precious stone of a pale dead green, with a mixture of yellow, sometimes of a fine yellow; and hence it was called chrysolite by the ancients, from its gold color. It is now considered by mineralogists as a variety of the sapphire.
3. Carbuncle, ברקת bareketh, from ברק barak, to lighten, glitter, or glister; a very elegant gem of a deep red color, with an admixture of scarlet. From its bright lively color it had the name carbunculus, which signifies a little coal; and among the Greeks ανθραξ anthrax, a coal, because when held before the sun it appears like a piece of bright burning charcoal. It is found only in the East Indies, and there but rarely.
4. Emerald, נפך nophech, the same with the ancient smaragdus; it is one of the most beautiful of all the gems, and is of a bright green color, without any other mixture. The true oriental emerald is very scarce, and is only found at present in the kingdom of Cambay.
5. Sapphire, ספיר sappir. See this described, Exodus 24:10.
6. Diamond, יהלם yahalom, from הלם halam, to beat or smite upon. The diamond is supposed to have this name from its resistance to a blow, for the ancients have assured us that if it be struck with a hammer, upon an anvil, it will not break, but either break them or sink into the surface of that which is softest. This is a complete fable, as it is well known that the diamond can be easily broken, and is capable of being entirely volatilized or consumed by the action of fire. It is, however, the hardest, as it is the most valuable, of all the precious stones hitherto discovered, and one of the most combustible substances in nature.
7. Ligure, לשם leshem, the same as the jacinth or hyacinth; a precious stone of a dead red or cinnamon color, with a considerable mixture of yellow.
8. Agate, שבו shebo. This is a stone that assumes such a variety of hues and appearances, that Mr. Parkhurst thinks it derives its name from the root שב shab, to turn, to change, "as from the circumstance of the agate changing its appearance without end, it might be called the varier." Agates are met with so variously figured in their substance, that they seem to represent the sky, the stars, clouds, earth, water, rocks, villages, fortifications, birds, trees, flowers, men, and animals of different kinds. Agates have a white, reddish, yellowish, or greenish ground. They are only varieties of the flint, and the lowest in value of all the precious stones.
9. Amethyst, אחלמה achlamah, a gem generally of a purple color, composed of a strong blue and deep red. The oriental amethyst is sometimes of a dove color, though some are purple, and others white like diamonds. The name amethyst is Greek, αμεθυστος, and it was so called because it was supposed that it prevented inebriation.
10. The Beryl, תרשיש tarshish. Mr. Parkhurst derives this name from תר tar, to go round, and שש shash, to be vivid or bright in color. If the beryl be intended, it is a pellucid gem of a bluish green color, found in the East Indies, and about the gold mines of Peru. But some of the most learned mineralogists and critics suppose the chrysolite to be meant. This is a gem of a yellowish green color, and ranks at present among the topazes. Its name in Greek, chrysolite, χρυσολιθος, literally signifies the golden stone.
11. The Onyx, שהם shoham. See Clarke's note on Genesis 2:12; See Clarke's note on Exodus 25:7. There are a great number of different sentiments on the meaning of the original; it has been translated beryl, emerald, prasius, sapphire, sardius, ruby, cornelian, onyx, and sardonyx. It is likely that the name may signify both the onyx and sardonyx. This latter stone is a mixture of the chalcedony and cornelian, sometimes in strata, at other times blended together, and is found striped with white and red strata or layers. It is generally allowed that there is no real difference, except in the degree of hardness, between the onyx, cornelian, chalcedony, sardonyx, and agate. It is well known that the onyx is of a darkish horny color, resembling the hoof or nail, from which circumstance it has its name. It has often a plate of a bluish white or red in it, and when on one or both sides of this white there appears a plate of a reddish color, the jewelers, says Woodward, call the stone a sardonyx.
12. Jasper, ישפה yashepheh. The similarity of the Hebrew name has determined most critics and mineralogists to adopt the jasper as intended by the original word. The jasper is usually defined a hard stone, of a beautiful bright green color, sometimes clouded with white, and spotted with red or yellow. Mineralogists reckon not less than fifteen varieties of this stone: 1. green; 2. red; 3. yellow; 4. brown; 5. violet; 6. black; 7. bluish grey; 8. milky white; 9. variegated with green, red, and yellow clouds; 10. green with red specks; 11. veined with various colors, apparently in the form of letters; 12. with variously coloured zones; 13. with various colors mixed without any order; 14. with many colors together; 15. mixed with particles of agate. It can scarcely be called a precious stone; it is rather a dull opaque rock.
In examining what has been said on these different precious stones by the best critics, I have adopted such explanations as appeared to me to be best justified by the meaning and use of the original words; but I cannot say that the stones which I have described are precisely those intended by the terms in the Hebrew text, nor can I take upon me to assert that the tribes are arranged exactly in the manner intended by Moses; for as these things are not laid down in the text in such a way as to preclude all mistake, some things must be left to conjecture. Of several of these stones many fabulous accounts are given by the ancients, and indeed by the moderns also: these I have in general omitted because they are fabulous; as also all spiritual meanings which others have found so plentifully in each stone, because I consider some of them puerile, all futile, and not a few dangerous.

And thou shalt set in it settings of stones,.... Or "fill in it fillings of stones" (d); which shows that there were in it ouches, or sockets of gold, the hollows of which were to be filled up with precious stones:
even four rows of stones; making a four square, and so filling up the measure of the breastplate:
the first row shall be a sardius, a topaz, and a carbuncle; about these stones, and those that follow, there is a great variety of interpretations of them, both among Jews and Christians; and they seem to be little known: our translators upon the whole seem to be as right as any in giving the names of them; the first of these, the "sardius", is a red stone of a blood colour, as the "cornelian" or "ruby", and which some have thought is here meant, and has its name either from the place where it has been found, Sardis or Sardinia; or rather from its red colour; for "sered" signifies red in Ezekiel 28:13 as Braunius (e) has observed from Kimchi; and so Odem, which is the word here used, signifies, and undoubtedly intends a stone of such a colour; and it is highly probable that this is the Demium of Pliny (f), which is one of the three kinds of sardius in India; and the red is so called from its redness, as the same Braunius observes. The second stone, the "topaz", had its name, according to Pliny (g), from an island in Arabia, in the Red sea, called Topazos; and the best topaz is the topaz of Cush or Arabia, as in Job 28:19. The topaz of the ancients was of a green colour; and so the three Targums call this stone Jarken or Jarketha, which signifies green; hence some have taken this to be the emerald, which is of a fine green colour: the third stone is the "carbuncle", as we render it; whatever stone is meant, it must be a bright and glittering one, like lightning, as the word signifies; wherefore some have taken it to be the emerald, so the Septuagint and Braunius (h); it being a very radiant and glittering stone, of a grass green, and very refreshing to the sight; but Danaeus (i) says, that the carbuncle is that species of the ruby, which of all is most beautiful and excellent, and darts out light like lightning to those that look at it at a distance, and shines in the middle of the night and darkness, so that it enlightens places near it, as if it were a sun:
this shall be the first row; now upon these three stones were engraven the names of Reuben, Simeon, and Levi, as both the Targums of Jonathan and Jerusalem agree.
(d) "et implebis in eo plenitudinem lapidis", Montanus; "vel eum impletione lapidis", Pagninus; "implebis in eo impletione lapidis", Drusius. (e) De Vestitu Sacerd. Hebrews. l. 2. c. 8. sect. 10. p. 639. (f) Nat. Hist. l. 37. c. 7. (g) Ibid. l. 6. c. 29. (h) Ut supra, (De Vestitu Sacerd. Hebrews. l. 2.) c. 10. sect. 4. p. 653. (i) Apud De Dieu in loc.

"And fill thereon (put on it) a stone-setting, four rows of stones," i.e., fix four rows of set jewels upon it. The stones, so far as their names can be determined with the help of the ancient versions, the researches of L. de Dieu (animadv. ad Ex 28) and Braun (vestit. ii. c. 8-10), and other sources pointed out in Winer's R. W. (s. v. Edensteine), were the following: - In the first or upper row, odem (σάρδιος), i.e., our cornelian, of a blood-red colour; pitdah, τοπάζιον, the golden topaz; bareketh, lit., the flashing, σμάραγδος, the emerald, of a brilliant green. In the second row, nophek, ἄνθραξ, carcunculus, the ruby or carbuncle, a fire-coloured stone; sappir, the sapphire, of a sky-blue colour; jahalom, ἴασπις according to the lxx, but this is rather to be found in the jaspeh, - according to the Graec., Ven., and Pers., to Aben Ezra, etc., the diamond, and according to others the onyx, a kind of chalcedony, of the same colour as the nail upon the human finger through which the flesh is visible. In the third row, lesehm, λιγύριον, lugurius, i.e., according to Braun and others, a kind of hyacinth, a transparent stone chiefly of an orange colour, but running sometimes into a reddish brown, at other times into a brownish or pale red, and sometimes into an approach to a pistachio green; shevo, ἀχάτης, a composite stone formed of quartz, chalcedony, cornelian, flint, jasper, etc., and therefore glittering with different colours; and achlaham, ἀμέθυστος, amethyst, a stone for the most part of a violet colour. In the fourth row, tarshish, χρυσόλιθος, chrysolite, a brilliant stone of a golden colour, not like what is now called a chrysolite, which is of a pale green with a double refraction; shoham, beryl (see at Genesis 2:12); and jaspeh, no doubt the jasper, an opaque stone, for the most part of a dull red, often with cloudy and flame-like shadings, but sometimes yellow, red, brown, or some other colour.