2. The Value of Golden Color

Ruri is determined to find gold, but Nagi explains that it might not be as likely as she hopes.

3. The Lost Planet

Ruri meets Nagi's colleague Imari, and the three embark on a journey to find a lost mine.

4. Study of Sands

In search of sapphire, Nagi teaches Ruri how to study sand, but Ruri prefers to hunt on a bigger scale.

5. Worlds Seen and Unseen

Ruri, Nagi, and Imari head to the beach in search of agate, and Ruri learns about the long lifecycle of rocks.

6. A Closer Look into the Blue

Just as the group begins searching for sapphire on foot, Ruri uncovers a grave mistake that halts their plans.

7. Seaside Recycling Studio

Ruri finds sea glass on the beach and runs into her classmate Shoko, who has a secret passion for minerals.

8. The Golden Elegy

Ruri teams up with Shoko for a science project, which takes a turn when they discover a strange, orange rock.

9. Time Capsule of 1.9 Million Tons

Ruri and Nagi head out to hunt for opals but discover that the area has already been fully excavated.

10. Sentence to an Abandoned Railroad

Imari leads a hunt for manganese ore, when the group encounters a mystery along abandoned railroad tracks.

11. The Sapphire Cradle

When Ruri has trouble deciding on her future, she turns to her study of sapphire.

12. Memories Come with Rocks and Noise

When Ruri discovers her grandpa's old crystal radio, she's determined to restore it.

13. Look Up, Examine, Search! And Next!

Ruri, Shoko, Nagi, and Imari take a trip together, where they search for meteorite at a hot springs inn.