Cloak of Beards

To many High Elves, the Cloak of Beards is a relic of an unhappy hour. But, for a few, notably those whose ancestors fought in Caledor II's final battle against Gotrek Starbreaker, it is a valued reminder of the perfidiousness of Dwarfs. This latter group ensure that the Cloak of Beards is never lost: indeed, with every generation, it grows longer and more fulsome, as more beards are seized and woven into its folds. Now, its power is such that its mere presence subverts prideful Dwarfen works.

Source

 * Warhammer Armies: High Elves (8th Edition) -- p. 65