Bud keeps rocks in his tattered suitcase because they are a memory of his deceased mother. At the beginning of the book, the reader does not understand the exact significance of the rocks with the writing on them. The reader simply knows that these rocks are a memory from Bud’s mom and that he keeps them in this treasured suitcase along with the picture of his mom and the flyer advertising Herman E. Calloway’s band performance. As the story progresses and Bud actually meets Herman E. Calloway, the reader realizes that the markings on the rocks are actually performance dates for the jazz band. Bud’s mom saved these rocks from the performances she attended (taken from each place the jazz band played) and passed them on to Bud as a special remembrance of his family. It is a touching gesture in Bud, Not Buddy when Bud offers these rocks to Calloway after finding out that Calloway is, in fact, his grandfather.