These will end up as a Hecatomb Cap as with all of the cursed gear you must complete the quest to remove it before you can use them, the end stats are as follows
Hecatomb Cap
(Head) All Races
DEF: 33 HP +12 STR +11 DEX +5
Slow +9%
Lv. 73 WAR / THF / PLD / DRK / BST / BRD / DRG
NPCs for ~16,488 gil, which you should put towards your psychiatric treatment, anger management classes and surgery to remove the tear-soaked Earth Crystal shrapnel from your face.