adamant

adj. unyielding, firm, immovable; hard

n. something unyielding, something immovable; something hard; stone similar to a diamond

Adamant and similar words are used to refer to any especially hard substance, whether composed of diamond, some other gemstone, or some type of metal. Both adamant and diamond derive from the Greek word αδαμας (adamas), meaning "untameable". Adamantite and adamantium (a metallic name derived from the Neo-Latin ending -ium) are also common variants.
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Noun
1. very hard native crystalline carbon valued as a gem
(synonym) diamond
(hypernym) carbon, C, atomic number 6
(hyponym) carbonado, black diamond
Adjective
1. not capable of being swayed or diverted from a course; unsusceptible to persuasion; "he is adamant in his refusal to change his mind"; "Cynthia was inexorable; she would have none of him"- W.Churchill; "an intransigent conservative opposed to every liberal tendancy"
(synonym) adamantine, inexorable, intransigent
(similar) inflexible

(n.)
Lodestone; magnet.
  

(n.)
A stone imagined by some to be of impenetrable hardness; a name given to the diamond and other substances of extreme hardness; but in modern mineralogy it has no technical signification. It is now a rhetorical or poetical name for the embodiment of impenetrable hardness.
  

To dream of adamant, denotes that you will be troubled and defeated in some desire that you held as your life.