Easton's Bible Dictionary: M. G. Easton, M.A., D.D.
(Heb.
shebo), a precious stone in the breast-plate of the high priest (
Ex. 28:19, 39:12), the second in the third row. This may be the agate properly so called, a semi-transparent crystallized quartz, probably brought from Sheba, whence its name. In
Isa. 54:12 and
Ezek. 27:16, this word is the rendering of the Hebrew cadcod, which means "ruddy," and denotes a variety of minutely crystalline silica more or less in bands of different tints.
This word is from the Greek name of a stone found in the river Achates in Sicily.