One of Achilles’ best known and most important connections with gold is that he rejects the treasure, including ten talents of gold (δέκα δὲ χρυσοῖο τάλαντα, Iliad 9.122 & 9.264), that is offered by Agamemnon as an inducement to rejoin the war effort. For he is in receipt of divine intelligence (from his mother Thetis, 9.410–416) that if he continues to fight at Troy he will die young, and his reward is to be immortal fame.
Provision for immortal fame involves, first, recognition from his peers, in the form of treasure-gifts, including spear-prize women, awarded by the army collectively (1.162) in recognition of meritorious service on the raids that bring in the treasure. After that, and in some measure depending on such signal honors, the hero can become a personage in heroic epic, which lasts forever. Agamemnon’s insulting and autocratic revocation of the army’s award of the woman has in effect broken the mechanism by which Achilles can hope for immortal fame. And as he himself points out, treasure itself cannot equally well be worth dying for, and cannot undo death:
cattle and fat sheep are things to be had for the lifting,
and tripods can be won, and the tawny high heads of horses,
but a man’s life cannot come back again, it cannot be lifted
nor captured again by force, once it has crossed the teeth’s barrier. (9.406–409, Lattimore trans.)
Another connection is the famous armor, particularly the shield, created for Achilles by Hephaestus at Iliad 18.478–607. Materials for the shield include bronze, tin, and silver as well, but the figuration or blazonry that dominates the passage prominently features gold.
The association of Hercules with gifts also raises questions. The song elsewhere uses gifts in the sense of talents (in the modern sense of extraordinary god-given abilities, not as weight or mass unit), and presumably is using it in that sense also in relation to Hercules—who is not so much known for gifts, in the sense of presents, as (say) the Magi of Christian myth.