Pumice

Pumice is an accessory in Final Fantasy IX. It is notable for being the only item to teach the Ark Summon, and for the difficulty in acquiring it: it is available only as a synthesis item after defeating Hades, or as a drop from Ozma, two of the strongest bosses in the game. Pumice Increases Speed by 1, Magic by 1, Defense by 1, and Magic Defense by 2. Ark takes 100 AP to learn.