The object possessed by the true dwarf king of Thraxon. It is a true silver crown, “inlayed with gold and precious stones, and on its top [is] a star sapphire as large as an egg” (3:341-342). It is imbued with magic.
During the reign of Set, it was broken to trap the ancient evil Mog within a mountain. When Alex destroyed Mog, the crown was revealed, and Alex took it with him. The dwarf smitty Bobkin of Joshua Taylor's bag—along with his fellow smittys—repaired the crown, with Alex adding the magic.
Alex returned it to King Thorgood, who by oath offered to Alex one-half of all the wealth of the dwarf realm of Thraxon or, alternately, one-half of the dwarf realm to rule in the dwarf king’s name. Alex, of course, did not accept, only requiring that the dwarfs support the Oracle of The Empty Tower. He promised that “if ever the dwarfs ... turn[ed] against the oracle, the crown [would] be lost once more” (3:460).