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Hastings' Dictionary of the New Testament [1]

(ἴασπις, from Assyr. aspû )

The king on the heavenly throne is like a jasper stone ( Revelation 4:3); the luminary of the New Jerusalem is like a stone most precious, as it were a jasper stone, clear as crystal (21:11); and the first foundation stone of the wall is a jasper. The jasper of mineralogy is an opaque, compact variety of quartz, variously coloured-red, brown, yellow, or green. As this stone does not answer the description ‘clear as crystal,’ some think that the diamond is meant (Smith’s Dict. of the Bible s.v. ), while others suggest the opal ( Encyclopaedia Biblica s.v. ). The ἴασπις of the Septuagint( Exodus 28:20) may have been the dark green jasper, which was known to the Egyptians and the early Greeks.

James Strahan.

Vine's Expository Dictionary of NT Words [2]

1: Ἴασπις (Strong'S #2393 — Noun Feminine — iaspis — ee'-as-pis )

a Phoenician word (cp. Heb. yash'pheh, e.g.,  Exodus 28:20;  39:16 ), seems to have denoted a translucent stone of various colors, especially that of fire,  Revelation 4:3;  21:11,18,19 . The sardius and the jasper, of similar color, were the first and last stones on the breastplate of the high priest,  Exodus 28:17,20 .

Morrish Bible Dictionary [3]

yashepheh, ἴασπις. This is not considered to be the same as the modern jasper, which is an opaque variety of quartz of many different colours. To what gem scripture refers is not known: some suppose the diamond. In  Revelation 21:11 it is described as 'clear as crystal.' It had a place in the high priest's breastplate, and was one of the stones in the covering of the symbolical king of Tyrus in Eden.   Exodus 28:20;  Exodus 39:13;  Ezekiel 28:13 . He who sat on the throne in heaven, as seen by John, was 'to look upon like a jasper;' it is also used in the description of the heavenly Jerusalem.  Revelation 4:3; Rev.21:11,18,19. The jasper is a symbol of the communicable glory of God. Compare  John 17:22 .

Smith's Bible Dictionary [4]

Jasper. A precious stone frequently noticed in Scripture. It was the last of the twelve inserted in the high priest's breastplate,  Exodus 28:20;  Exodus 39:13, and the first of the twelve used in the foundations of the new Jerusalem.  Revelation 21:19.

The characteristics of the stone, as far as they are specified in Scripture,  Revelation 21:11, are that it "was most precious," and "like crystal;" we may also infer from  Revelation 4:3, that it was a stone of brilliant and transparent light. The stone which we name "Jasper" does not accord with this description. There can be no doubt that the Diamond would more adequately answer to the description in the book of Revelation.

Fausset's Bible Dictionary [5]

Last of the gems in the high priest's breast-plate ( Exodus 28:20), probably the green jasper. In  Revelation 21:19 it is first of New Jerusalem's foundations. It represents watery crystalline brightness, symbol of purity:  Revelation 21:11, "her light was like unto a stone most precious, even like a jasper stone, clear as crystal." "He that sat upon the throne ( Revelation 4:3) was to look upon like a jasper." Ebrard thinks the diamond is meant. The common jasper has various wavy colors, somewhat transparent. The king of Tyre ( Ezekiel 28:13) has the jasper with eight other of the high-priest's 12 precious stones, as type of antichrist who usurps Christ's high-priesthood combined with kingship ( Zechariah 6:13).

Watson's Biblical & Theological Dictionary [6]

ישפה ,  Exodus 28:20;  Exodus 39:13; and  Ezekiel 28:13; ιασπις ,  Revelation 4:3;  Revelation 21:11;  Revelation 21:18-19 . The Greek and Latin name, jaspis, as well as the English jasper, is plainly derived from the Hebrew, and leaves little room to doubt what species of gem is meant by the original word. The jasper is usually defined, a hard stone, of a bright, beautiful, green colour; sometimes clouded with white, and spotted with red or yellow.

King James Dictionary [7]

J`ASPER, n. L. iaspis. A mineral of the siliceous kind, and of several varieties. It is less hard than flint or even than common quartz, but gives fire with steel. It is entirely opake, or sometimes feebly translucent at the edges, and it presents almost every variety of color. Its varieties are common jasper, striped jasper, Egyptian jasper, &c. It admits of an elegant polish, and is used for vases, seals, snuff-boxes, &c.

Jasper is a subspecies of rhomboidal quartz, of five kinds, Egyptian, striped, porcelain, common, and agate jasper.

Holman Bible Dictionary [8]

 Ezekiel 28:13 Exodus 28:20 Exodus 39:13 Ezekiel 28:13 Revelation 4:3 Revelation 21:11 21:18-19 Job 28:18Minerals And Metals

People's Dictionary of the Bible [9]

Jasper. The last stone in the breastplate of the high priest, and the first in the foundations of the new Jerusalem.  Exodus 28:20;  Revelation 21:19. Jasper is an opaque species of quartz, of different colors, often banded or spotted, and susceptible of a high polish. The dark-green kind is supposed to be the variety of the Bible.

Wilson's Dictionary of Bible Types [10]

 Revelation 4:3 (c) Probably a very valuable stone, translucent or transparent, typical of the preciousness of our GOD in whom there is no flaw, defilement, evil, nor spot of any kind. He was beautiful, precious, valuable and attractive. (See also  Revelation 21:11).

Webster's Dictionary [11]

(n.) An opaque, impure variety of quartz, of red, yellow, and other dull colors, breaking with a smooth surface. It admits of a high polish, and is used for vases, seals, snuff boxes, etc. When the colors are in stripes or bands, it is called striped / banded jasper. The Egyptian pebble is a brownish yellow jasper.

American Tract Society Bible Dictionary [12]

A precious stone of various colors, as green, purple, etc., often clouded with white, and beautifully striped with red or yellow,  Exodus 28:20;  Revelation 4:3;  21:11 .

Easton's Bible Dictionary [13]

 Exodus 28:20 Revelation 21:18,19

Hastings' Dictionary of the Bible [14]

JASPER . See Jewels and Precious Stones, p. 467 a .

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [15]

( י שְׁפֶה ,Yashepheh', Prob. Polished Or Glittering, Ἴασπις ), a gem of various colors, as purple, cerulean but mostly green like the emerald, although duller in hue (Plily, Nat. Hist. 37: 8, 9; Epiphaluius, De Gemmis, § 6; Braun, De Vest. Sacerdot. 2, 19). "It was the last of the twelve inserted in the high-priest's breastplate ( Exodus 28:20;  Exodus 39:13), and the first of the twelve used in the foundation of the new Jerusalem ( Revelation 21:19): the difference in the order seems to show that no emblematical importance was attached to that feature. It was the stone employed in the superstructure ( Ἐνδόμησις ): of the wall of the new Jerusalem ( Revelation 21:18). It further appears among the stones which adorned the king of Tyre ( Ezekiel 28:13). Lastly, it is the emblematical image of the glory of the divine Being ( Revelation 4:3). The characteristics of the stone, as far as they are specified in Scripture ( Revelation 21:11) rare that it was.' most precious,' and like crystal' ( Κρυσταλλίζων ); not exactly clear as crystal,' as in the A.V., but of a crystal hue: the term is applied to it in this sense by Dioscorides (5. 160: Λίθος Ἰάσπις Μὲν Τίς Ἐστι Σμαραγδιζων Δὲ Κρυσταλλ Ó Δης ). We may also infer from  Revelation 4:3 that it was a stone of brilliant and transparent light." The ancient jasper thus appears to have been frequently translucent, but the modern is opaque. A brown variety existed in Egypt. The jasper of the ancients, therefore, comprehended various precious stones not readily identifiable (Rosenm Ü ller, Bibl. Alterthum, IV, 1, 42; Moore's Anc. Min. p. 163). What is now properly called jasper by mineralogists is a sub-species of rhomboidal quartz, of several varieties, mostly the common, the Egyptian, and the striped; of different colors-whitish; yellow, green, reddish, etc., sometimes spotted or banded; occurring either in masses or loose crystals, and susceptible of a fine polish (see the Lond. Encyclopedia, s.v.). (See Gemi).

Kitto's Popular Cyclopedia of Biblial Literature [16]

Our word Jasper is plainly from the Greek jaspis, which comes from the Hebrew word yashpeh. Jasper is a species of the quartz family, and embraces a great many varieties. The brown Egyptian variety was perhaps the one selected for the breastplate of the high-priest . The brown is of various shades, disposed in concentric stripes. It occurs loose in the sands of Egypt, and is cut into ornaments.

The Nuttall Encyclopedia [17]

An opaque quartz found in all colours, and spotted, striped, and clouded; is valued in ornamental lapidary work because of the polish it takes.