In the mountains, while searching for minerals, a high school girl named Ruri encounters Nagi, a graduate student.

Ruri was resolute in her quest for gold, yet Nagi offered a sobering perspective, suggesting the prospect might prove less attainable than she desired.

Ruri encountered Imari, a colleague of Nagi’s, and together they set out on a quest for a mine long since lost.

Seeking sapphire, Nagi instructs Ruri in the art of sand study; however, Ruri favors a more expansive approach to her pursuits.

Ruri, Nagi, and Imari set off for the beach, hoping to find agate among the stones. There, Ruri begins to understand the protracted history held within each rock.

As the party commenced their search for sapphire on foot, Ruri stumbled upon a grave error, one that brought their endeavors to a standstill.

The beach yielded its treasures to Ruri in the form of sea glass, smooth and frosted by the relentless ocean. As she gathered her finds, she encountered Shoko, a classmate whose quiet demeanor concealed a deep and fascinating passion for mi…

Ruri joined forces with Shoko on a science project, but their endeavor took an unexpected turn upon discovering a peculiar, orange rock.

Ruri and Nagi set out in search of opals, only to find the region already stripped bare by previous excavations.

Imari guides the expedition in search of manganese ore, but their quest takes an unexpected turn when they stumble upon an enigma hidden amongst the derelict railway lines.

Faced with the uncertainty of her path, Ruri finds solace in her study of sapphires.

Upon finding her grandfather’s forgotten crystal radio, Ruri resolved to bring it back to life.

Ruri, Shoko, Nagi, and Imari journey together, seeking a meteorite at a secluded inn known for its thermal waters.