青のマテリア [ao no materia] or 'blue materia' in Japanese.
Final Fantasy Tactics

Obtain: randomly from one of the following Errands: Gariland Magick Melee, Mount Gulg Mother Lode, Zaland Embassy Antiques, Abandoned Mine, Clockwork Faire, Salvage Expedition, Zerro's Challenge, Guard Duty, Yardrow Melee, Gleddia Isle, Lettre d'Amour, Count Minimas (1), Count Minimas (2), The Durga, Endless Caverns, The Falcon, Father's Nightmare, Himca Cliffs, More Coal Miners Wanted, Ore of the Gods, Past Glory, Rhana Strait, True Romance, Zerro's Return, Zerro Strikes, Zerro Strikes Again, Appraisal, Gysahl Greens, Historic Revolt, Lionel Emissary, Second Coal Mining Expedition
Type: Artefact
Description: These stones, developed by the ancient Saronians, are the result of experiments in storing knowledge within gems for later generations. They are said to enhance the abilities of the possessor.
Airborne Brigade

Use: Transmute Operation Jenova abilities from R to R+ and R+ to SR
Buy: - (sell: -)
Drop: event bosses
Obtain: randomly from daily log-in bonus, ranking rewards
Category: Item