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Adamant
NET Glossary: a somewhat archaic or poetic term for the very hardest substance, like diamond (there is no evidence that diamond as a material was known in antiquity)
Adamant [EBD]
(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).
ADAMANT [SMITH]
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.ADAMANT [ISBE]
ADAMANT - ad'-a-mant (shamir (Ezek 3:9; Zec 7:12)): In the passages cited and in Jer 17:1, where it is rendered "diamond" the word shamir evidently refers to a hard stone. The word adamant ("unconquerable") is used in the early Greek writers for a hard metal, perhaps steel, later for a metal-like gold and later for the diamond. The Hebrew shamir, the Greek adamas (from which word "diamond" as well as "adamant" is derived) and the English adamant occur regularly in figurative expressions. All three are equally indefinite. Adamant may therefore be considered a good translation for shamir, though the Septuagint does not use adamas in the passages cited. There is a possible etymological identification of shamir with the Greek smyris (smeris or smiris), emery, a granular form of corundum well known to the ancients and used by them for polishing and engraving precious stones. Corundum in all its forms, including the sapphire and ruby, is in the scale of hardness next to the diamond. In English Versions of the Bible Isa 5:6; 7:23-25; 9:18; 10:17; 27:4; 32:13, shamir is translated "brier".Alfred Ely Day
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