Adamant
is really the mineral corundum; but the word is indifferently used for rock crystal, diamond, or any hard substance, and also for the magnet or loadstone. It is often used by poets for no specific substance, but as hardness or firmness in the abstract. Thus, Virgil, in his Æneid vi. 552, speaks of “adamantine pillars” merely to express solid and strong ones; and Milton frequently uses the word in the same way. Thus, in Paradise Lost, ii. 436, he says the gates of hell were made of burning adamant:
Ninefold, and gates of burning adamant
“He [Satan] hasted, and opposed the rocky orb
Of ten-fold adamant, his ample shield
A vast circumference.”
(“Plantage to the moon,” from the notion that plants grew best with the increasing moon.)
“As true to thee as steel to adamant.”
“To-morrow about noon we shall be near the black mountain, or mine of adamant, which at this very minute draws all your fleet towards it, by virtue of the iron in your ships.”