Ruri no Houseki
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Episodes (13)
EP 1Ruri seeks affordable quartz and learns geology with Nagi's help
Jul 6, 2025Unable to afford a quartz point necklace, student Ruri travels to the mountains to find crystals herself. There, she encounters Nagi, a graduate geologist who arrives in a Mini Cooper armed with a medieval European war hammer for sampling difficult rock formations. Under Nagi's guidance, Ruri successfully collects a quality quartz cluster and a bag of pigeon-blood garnets. Beyond the minerals, she gains fundamental understanding of pegmatites, plate tectonics, and erosion processes. This experience ignites a strong interest in earth sciences, leading Ruri to desire a rock hammer for future exploration.
EP 2Ruri Prospects for Gold and Discovers the Difference Between Cash and Scientific Value
Jul 13, 2025Nagi accompanies Ruri to a gold prospecting district where she practices with a rock hammer. Although Ruri becomes skilled, her split stones reveal only pyrite, a fact confirmed by a streak test. The discovery of a uniquely shaped crystal leads to a conversation regarding the distinction between monetary worth and scientific importance. Later, the pair attempts panning for placer gold in a stream bed, achieving improved results following a heavy rain. Their search of a pothole uncovers additional gold, including a large nugget that Ruri prefers to retain rather than sell.
EP 3Nagi and Ruri explore a university lab and discover a mysterious bismuth crystal alongside an old map.
Jul 20, 2025Nagi takes Ruri to her university laboratory, introducing her to colleague Yoko. Nagi reveals she co-authored a paper on a pyrite crystal Ruri found. While cleaning, Ruri discovers a strange bismuth crystal and an old topographic map highlighting an unmapped mine. The trio travels to the site, using a magnet to locate iron ore in the tailings. They fall into a collapsed tunnel section and must navigate through the passages to escape. Inside, Nagi uses an ultraviolet flashlight to reveal a previously unrecorded galaxy of fluorite crystals. Impressed by the discovery, Nagi encourages Yoko to lead a formal study on the new mineral formation.
EP 4Ruri uses magnetism to accelerate sapphire source analysis while Yoko studies fluorites.
Jul 27, 2025Ruri searches for sapphires by analyzing river sand, which Nagi explains recapitulates the geology of upstream drainages. The standard method involves examining sand from each tributary and recording results under a binocular microscope, a process requiring hours of work. To save time, Ruri discovers a shortcut by running a magnet over the sample to remove the magnetic fraction. Meanwhile, Yoko focuses on her fluorites, which may contain tungsten. As Ruri dedicates her efforts to this geological investigation, her friends begin to wonder how she is spending her free time.
EP 5Ruri, Yoko, and Nagi explore a gravel beach for rocks and minerals.
Aug 3, 2025Ruri, Yoko, and Nagi search a gravel beach, finding banded agates and other forms of quartz. Nagi speaks of rocks as fascinating clues to the formation and history of the world. A fleck of silvery metal proves anomalously dense in a simple test. It might be platinum, which is less rare in serpentinite from the Earth's mantle. Nagi provides a short review of volcanism and plate tectonics. In the mountains they find a big shiny block of serpentinite, and more platinum grains in a nearby stream.
- 6EP 6
Ruri and friends locate the sapphire deposit after correcting a note error near a shrine.
Aug 10, 2025Ruri identifies the watershed containing the sapphire deposit, prompting a trip with Nagi and Yoko to the location. After visiting a shrine, their initial foot search proves difficult due to fallen leaves obscuring the ground. Ruri discovers an error in her notes, which they correct through additional sand searches to better pinpoint the deposit. Upon climbing to a ridgeline, they find plentiful sapphires, leading Nagi to explain their geological origin. An old inscription reveals a missed clue regarding the shrine's name. Additionally, Ruri is shown wearing more suitable clothing and shoes for outdoor work, though this detail is not explicitly mentioned in the narrative.
- 7EP 7
Shoko finds friends while exploring sea glass and silica color science with Ruri.
Aug 17, 2025Schoolgirl Shoko has a passion for rocks but lacks support until she meets Ruri and her group, who are investigating sea glass. The episode explains how silica glass acquires different colors, specifically through the phenomenon of thin-film interference. During a day spent searching for old bottles on the beach, Shoko makes new friends who share her interest. Additionally, Ruri discovers that her name is an archaic term for blue glass, adding a personal layer to the day's discoveries and strengthening the bond between the characters.
- 8EP 8
Shoko and Ruri investigate water quality and discover orange crystals at an abandoned factory.
Aug 24, 2025Shoko conducts water quality tests for a school science project, with Ruri joining her efforts. During their sampling, Shoko discovers an orange crystal but subsequently loses it. Meanwhile, Yoko performs similar water tests to identify a new fluorite deposit. These investigations eventually guide the group to an abandoned factory. Inside the facility, they locate rare orange zincite. This mineral serves as a decorative item and symbolizes the friendship between Shoko and Ruri. The narrative focuses on their scientific exploration and the discovery of these specific minerals within the industrial setting.
- 9EP 9
Team discovers opals at dam after investigating riverbank waste and quartz sources
Aug 31, 2025Ruri feels let down when a reported opal deposit proves to be completely exhausted. Heavy rainfall washes cultural debris onto the riverbank, bringing along unexpected quartz and pyrite. Nagi organizes a spontaneous fashion show during this time. The group heads back to the river to investigate further upstream. They locate the origin of the quartz and pyrite. Continuing their search, they reach a dam site where water flow has concentrated abundant opals, resolving their earlier disappointment with a significant discovery.
- 10EP 10
Geologists explore abandoned manganese mine and discover toxic rhodonite ballast
Sep 7, 2025A geological team led by Yoko visits a historical manganese mine after Nagi misses the trip. They study manganese properties but are blocked by a collapsed tunnel. Searching nearby tracks, they find large quantities of rhodonite and rhodochrosite. This suggests prohibited toxic tailings were used as track ballast, possibly by a past crew for emergency repairs. The true reason for this usage remains unknown.
- 11EP 11
Ruri uses gem analysis to resolve her course selection dilemma
Sep 14, 2025Struggling to choose elective courses, Ruri observes Yoko creating thin slates for polarized light examination. She applies this technique to sapphires to understand their formation, then returns to the field to locate the original host rock. Hydrochloric acid testing identifies calcite, and further searching guided by the old shrine story reveals more sapphires and a plausible geological history. Gaining confidence and self-knowledge through this process, Ruri ultimately decides to study Earth science.
- 12EP 12
Ruri discovers a crystal radio among her grandfather's belongings and attempts to build one with friends.
Sep 21, 2025While sorting through her grandfather's possessions, Ruri uncovers a device made of copper wires and crystals. Nagi recognizes the item as a crystal radio. Ruri, Shoko, and their new friend Aoi attempt to replicate the device but face difficulties locating the appropriate mineral for the detector. They eventually succeed by using a germanium diode, which verifies that their construction is accurate. The group finds that a nearby shrine, which holds significance for Ruri's family, provides superior signal reception for their creation.
- 13EP 13
Geologists visit a hot spring hotel and discover cosmic spherules in rooftop dust.
Sep 28, 2025Geologists stay at an upscale hot-spring hotel where they identify a white stone ring as lime deposited from the spring water. Nagi discusses professional prospects for geologists, and the group observes shooting stars at night. She explains that rooftop dust might contain micrometeorites collectible with a magnet. Using a microscope, they locate a cosmic spherule. Ruri reflects on the enjoyment of scientific discovery and anticipates future findings.
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Frequently asked questions
- How many episodes does Ruri no Houseki have?
- Ruri no Houseki has 13 episodes.
- When did Ruri no Houseki come out?
- Ruri no Houseki came out in 2025.
- Which studio made Ruri no Houseki?
- Ruri no Houseki was produced by Studio Bind.
- Who directed Ruri no Houseki?
- Ruri no Houseki was directed by Shunichirou Yoshihara.
- Is Ruri no Houseki finished?
- Current status of Ruri no Houseki: Finished.