Phoenix Crown

The Phoenix Crown is the revered symbol of office for the Elven Phoenix King of Ulthuan. The original crown was created during the time of Aenarion. It was forged not from a single piece of metal, but was crafted from ingots of gold and gemstones brought from the ten kingdoms. From the very start, it was deemed that the Phoenix Crown should be derived from all the realms it was to rule.

Caledor II was the first, and only, Phoenix King ever to wear the crown in battle. So assured of his superiority was Caledor that he refused to believe any foe had the strength of arms to wrest it from him. The folly of this course was later proved when the Dwarf King Gotrek Starbreaker took the crown from Caledor's corpse as spoils of war and as recompense for insults suffered. Thus lost in battle, the first Phoenix Crown was never recovered. Even to this day, it rests amidst the hoards of Karaz-a-Karak, a fond memento for the Dwarfs, and an aching wound to High Elf pride.

After his own rise to the Phoenix Throne, Caradryel soon determined that a replacement crown should be commissioned. The task of forging fell to the priests of Vaul, who undertook the work with all the diligence for which their order was famous and, after a century's labour, the new crown was completed. Mindful of Caledor's impetuousness, Caradryel's first decree whilst wearing the new Phoenix Crown was that this new symbol of Elven kingship would never enter the fires of battle. Furthermore, he announced that the crown would henceforth have a guard of one hundred White Lions of Chrace to watch over it at all times.

Source

 * Warhammer Armies: High Elves (8th Edition) -- p. 21