Stone with mystical power.
Shaman Stone is an item that can be obtained by refining either 1 Rosetta Stone, Hungry Cookpot, Mog's Amulet, or Dark Matter. One Shaman Stone can be refined into one LuvLuvG via Tool-RF, ten Shaman Stones can be refined into one Holy War-trial via Forbid Med-RF as long as Doomtrain is at level 100, and one Shaman Stone can be refined into one Rosetta Stone.
Alchemists all over Vana'diel search for these stones. Invaluable as an ingredient in high level alchemy.
Philosopher's Stone is a synthesis item used to make Alchemist's Water, Panacea, Sun Water, and Saline Broth. It is used in the "Her Memories: Of Malign Maladies" and "Titillating Tomes" quests.
A stone made of the blood of ancient gods. Listen closely to hear their wails.
Seer Stone is an accessory that provides 3 Magic, 2 Magic Resistance, and 3 Jewel slots.