Pirates of the Spanish Main and the other versions of this strategy game include unique treasure pieces. They seem to be a bit rare, for I have only received two unique treasure pieces in six game packs. Unique treasures, like normal treasure are distributed among the “wild Islands”.
Unique treasures are worth 0 gold pieces, but may change later in the game. Unique treasures provide the ship in which they are carried special abilities.
Special abilities like the two listed here: