From BiblePortal Wikipedia

Vine's Expository Dictionary of NT Words [1]

1: Χρυσόπρασος (Strong'S #5556 — Noun Masculine — chrusoprasos — khroo-sop'-ras-os )

from (chrusos, "gold," and prasos, "a leek"), is a precious stone like a leek in color, a translucent, golden green. Pliny reckons it among the beryls. The word occurs in  Revelation 21:20 .

Watson's Biblical & Theological Dictionary [2]

 Revelation 21:20 , a precious stone, which Pliny classes among the beryls; the best of which, he says, are of a sea-green colour; after these he mentions the chrysoberyls, which are a little paler, inclining to golden colour; and next, a sort still paler, and by some reckoned a distinct species, and called chrysoprasus.

Fausset's Bible Dictionary [3]

("gold leek".) A transparent gem, an agate of the color of the leek's juice; it owes its color to oxide of nickel. Found only in Silesia; also in antique Egyptian jewelry. The garniture of the tenth foundation of New Jerusalem ( Revelation 21:20).

People's Dictionary of the Bible [4]

Chrysoprasus, Golden Green. A precious stone probably allied to the beryl, usually of a greenish-golden color.  Revelation 21:20. R. V., Chrysoprase .

American Tract Society Bible Dictionary [5]

The tenth of those precious stones which adorned the foundation of the heavenly Jerusalem, as seen by John the Evangelist. Its color was green, inclining to gold, as its name imports,  Revelation 21:20 .

Morrish Bible Dictionary [6]

Supposed to be a variety of Chalcedony of a green shade.  Revelation 21:20 . The word χρυσόπρασος does not occur in the LXX.

Easton's Bible Dictionary [7]

 Revelation 21:20

Webster's Dictionary [8]

(n.) See Chrysoprase.

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [9]

( Χρυσόπρασος , mentioned in  Revelation 21:20, as the tenth row of stones in the foundation of the heavenly Jerusalem), a precious stone of greenish-golden color, or apple-green, passing into a grass-green (Pliny, Hist. Nat. 27 : 20, 21); an Indian translucent gem, so called as resembling in color the juice of the leek ( Πρἀσον ), with golden spots ( Χρυσός ) a species of beryl, supposed to be possessed of healing power in diseases of the eyes. Its spotted character may be inferred from the name given to it by Pliny ( Hist. Nat. 37, c. 8), Pardalios, or, rather, Pantherion, from its resembling the leopard-skin (see Braun. De Vest. Sac. Hebrews 2 , c. 9, p. 509). The chrysoprase of the ancients is by some supposed to be identical with the stone now so called, viz. the apple or leek-green variety of agate, or uncrystallized quartz ( London Encyclopaedia, s.v.), which owes its color to oxide of nickel; this stone at present is found only in Silesia; but Mr. King (Antique Gems, p. 59. note) says that the true chrysoprase is sometimes found in antique Egyptian jewelry set alternately with bits of lapis-lazuli. (See Gem).

In  Genesis 2:12, the Sept. renders the word שֹׁהִם , Sho'Ham, by chrysoprase ( Λίθος Πράσινος ), but they were probably different gems. (See Beryl).

Kitto's Popular Cyclopedia of Biblial Literature [10]

Chrysop´rasus. This occurs only in . The name literally signifies 'leek-green stone,' and it is, as that name imports, of a greenish golden color like a leek, that is usually apple-green passing into grass green.