Quite a few of the new weapons have this enchantment. Example:
Steel-splitter
Level: 72
Slot: Weapon
Type: Pole
Jobs: DRG MNK PLD WHM
Races: All
Damage: 64
Delay: 412
Damage Per Second (DPS): 9.32
TP Per Hit: 10.44%
Auction House Category:
Weapons / Staves
Effects for Steel-splitter:
* Dexterity +2
* HP Regeneration While Healing +3
* Enchantment: Stone
<Max Charges: 50 / Equip Delay: 30s / Reuse Timer: 10m>
But what does that do? does it cast a spell? is it a special buff?