Where to find and use Adamantite in Final Fantasy Resonance

In Final Fantasy Resonance, Adamantite is a key item found in mid- and end-game areas that you trade to the weaponsmith Aileen to craft powerful weapons for your party. There are eight Adamantite in total, located in places like Oblivion Palace, Olderion, a roaming merchant ship, Gronoa's Rugged Mountain Path, and the Grandshelt Colosseum. Starting in Chapter 6, Aileen asks which character you want a weapon for, and each character receives a distinct weapon with its own effect.