Tokyo, Japan – The fifth episode of the popular anime series Ruri Rocks, titled “Worlds Seen and Unseen,” premiered on Sunday, August 3, 2025, at 9:30 p.m. JST on Tokyo MX and other local Japanese television networks. International audiences can stream the episode on Crunchyroll, while Aniplus Asia is streaming the series in Southeast Asia.
The latest installment sees protagonists Ruri, Nagi, and Imari venturing to the beach in pursuit of agate, a common yet fascinating mineral. The episode further delves into the educational core of the series, focusing on Ruri’s growing understanding of the extensive lifecycles of rocks and the scientific methodologies behind mineralogy.
Release Details and Streaming Availability
Ruri Rocks Episode 5, “Worlds Seen and Unseen,” made its initial broadcast in Japan on August 3, 2025. For viewers outside of Japan, Crunchyroll is the primary platform for streaming the series, making episodes available shortly after their Japanese airing. Aniplus Asia has secured licensing for the series in Southeast Asia.
The anime, which has garnered attention for its unique blend of “cute girls doing cute things” (CGDCT) and educational content focused on geology and mineralogy, has a running time of approximately 23 minutes per episode.
Episode 5 Plot Highlights
Following Ruri’s diligent efforts in the previous episode to study collected sand for sapphires, “Worlds Seen and Unseen” shifts the setting from the lab to a beach excursion. The trip, initiated by Ruri with the intention of fun, seamlessly integrates into the ongoing geological exploration.
In this episode, the trio’s search for agate provides Nagi, the knowledgeable graduate student in mineralogy, an opportunity to explain the origins and complexities of these beautiful quartz iterations. The narrative underscores Nagi’s passion for cataloging and understanding the broader geological formations, rather than merely collecting rare specimens, reinforcing the series’ commitment to authentic scientific adventure based on the author’s solid knowledge of mineralogy.
Background of the Ruri Rocks Anime
The Ruri Rocks anime, known in Japan as Ruri no Hōseki (meaning “Ruri’s Jewels” or “Introduction to Mineralogy”), is an adaptation of the manga series written and illustrated by Keiichirō Shibuya. The manga began serialization in Enterbrain’s Harta magazine in August 2019.
Studio Bind is producing the anime television series, with Shingo Fujii directing and Michiko Yokote handling series composition. The story follows high school student Ruri Tanigawa, who, driven by her love for jewelry, discovers the fascinating world of mineralogy after encountering graduate student Nagi Arato. The anime premiered on July 6, 2025, on AT-X and other networks. The series is praised for its beautiful animation, gentle character dynamics, and intriguing geological information.
