Beanstone

A Beanstone is an item that Mario and Luigi find in Mario & Luigi: Superstar Saga. It is optional, however. It appears in random spots of the Beanbean Castle Town, after talking to a Beanbean scholar. If the Mario Bros. collect them all and return them to the scholar, then the scholar will give the Mario Bros. a Bros. Rock badge. After Cackletta's second invasion of the place, then this sidequest is not open.