Agate: (Heb. shebo), a precious stone in the breast-plate of the high priest
(Exodus 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
(Isaiah 54:12) and
(Ezekiel 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.