Adamant
Smith’s Bible Dictionary (1863)
the translation of the Hebrew word Shamir in (Ezekiel 3:9) and Zech 7:12 In (Jeremiah 17:1) it is translated “diamond.” In these three passages the word is the representative of some stone of excessive hardness, and is used metaphorically. It is very probable that by Shamir is intended emery, a variety of corundum, a mineral inferior, only to the diamond in hardness.
Easton’s Bible Dictionary (1897)
(Heb. shamir), Ezek. 3:9. The Greek word adamas means diamond. This stone is not referred to, but corundum or some kind of hard steel. It is an emblem of firmness in resisting adversaries of the truth (Zech. 7:12), and of hard-heartedness against the truth (Jer. 17:1).
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