Strong's #5306: nophek (pronounced no'-fek)

from an unused root meaning to glisten; shining; a gem, probably the garnet:--emerald.

Brown-Driver-Briggs Hebrew Lexicon:

nôphek

1) a precious stone in the high priest' s breastplate

1a) perhaps an emerald, turquoise, ruby, or carbuncle

2) jewels imported from Tyre

Part of Speech: noun masculine

Relation: from an unused root meaning to glisten

Usage:

This word is used 4 times:

 

Exodus 28:18: "And the second row shall be an emerald, a sapphire, and a diamond."
Exodus 39:11: "And the second row, an emerald, a sapphire, and a diamond."
Ezekiel 27:16: "by reason of the multitude of the wares of thy making: they occupied in thy fairs with emeralds, purple, and embroidered work, and fine linen,"
Ezekiel 28:13: "the onyx, and the jasper, the sapphire, the emerald, and the carbuncle, and gold: the workmanship of thy tabrets"