Key Points of Presentation
◆ A new mineral has been discovered within jadeitite, a representative stone of Japan and a symbol of Japanese stone culture.
◆ The mineral is named amaterasuite, after Amaterasu Omikami, the goddess of the sun in Japanese mythology.
◆ The discovery of amaterasuite has given rise to new perspectives on jadeitite and attracted attention as a tangible example linking crystallographic theory with observation.
Overview
A research team has discovered a previously unrecognized mineral within jadeitite, designated as “a representative stone of Japan” by the Japan Association of Mineralogical Sciences (JAMS). The research team consisted of Daisuke Nishio-Hamane, Technical Specialist, Institute for Solid State Physics, University of Tokyo; Mariko Nagashima, Young Advanced Professor, Graduate School of Science and Technology for Innovation, Yamaguchi University; Yuki Mori, Researcher, Japan Synchrotron Radiation Research Institute (JASRI); Norimasa Shimobayashi, Professor, Graduate School of Science, Kyoto University; Takashi Matsumoto, Group Manager with Rigaku Corporation, a Group company of Rigaku Holdings Corporation; and Masayuki Ohnishi and Mitsuo Tanabe, amateur mineralogists.
The team decided to name the mineral newly discovered within jadeitite “amaterasuite,” in honor of Amaterasu Omikami, the sun goddess of Japanese mythology. Amaterasuite is now recognized by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA-CNMNC)1.
These research findings were reported in the August 7, 2025 edition of the Journal of Mineralogical and Petrological Sciences, published by JAMS.
Reported Findings
Background
Jadeitite has been used since ancient times, as a tool for its durability and fine grain and as ornaments and jewelry for its beauty. Japan’s culture of jadeitite use is known to be the oldest in the world. In mineralogical and petrological terms, jadeitite is only formed in subduction zones2, such as deep interior beneath the Japanese archipelago. It is a rare type of rock that tells the tale of the Earth’s tectonic activity. In light of its cultural and scientific importance, in 2016 JAMS designated jadeitite Japan’s “a representative stone of Japan3.”
Jadeitite is mainly formed as a mineral called jadeite. Minerals present in jadeitite in small quantities are known to be rich in elements such as strontium (Sr) and titanium (Ti). Previous studies focusing on this characteristic had led to the discovery of new minerals such as rengeite and matsubaraite4. For many years, theses minerals were thought to be unique to jadeitite found in the Itoigawa area of Niigata Prefecture. More recently, however, those have been confirmed to occur from jadeitite found in the Osayama area of Okayama Prefecture. Moreover, Osayama jadeitite is now known to contain several minerals that were previously unknown. One of these is the new mineral recognized on this occasion, namely amaterasuite (Figure 1).
What is amaterasuite?
Establishing a new mineral species, it must be proven to differ from known minerals in chemical composition, crystal structure, or both. Amaterasuite, being novel in both chemical composition and crystal structure, leading IMA-CNMNC to approve it as a new mineral.
The ideal formula of amaterasuite is expressed by Sr4Ti6Si4O23(OH)Cl, indicating that its main components are strontium, titanium, silicon, oxygen, hydrogen and chlorine. This ratio among elements is unique, being reported in no other mineral, suggesting the existence of a wholly new formation reaction.
Minerals are products of geological events. The discovery of new mineral often points to the existence of previously unknown geological processes and environments. While jadeitite was already known to be formed in subduction zones, the discovery of new mineral such as amaterasuite presents fresh perspectives on the origins and evolution of jadeitite.
The crystalline structure of amaterasuite has been determined with great precision. This feat was made possible by X-ray powder diffraction using beamline BL02B2 of SPring-8, a large-scale synchrotron radiation facility5, and by fine diffraction using Synergy-DW, a high-end monocrystal structural analyzer produced by Rigaku Corporation and owned by Yamaguchi University.
These findings revealed a characteristic of the crystalline structure of amaterasuite that deserves special mention. Namely, the structure is characterized by a dual nature, encapsulating two types (A and B) within a unit cell (Figure 2). Although this crystal structure found in amaterasuite had been predicted theoretically, it had never been observed in practice until this study. These results greatly advanced science’s understanding of the true diversity of crystal structures.
In summary, the discovery of amaterasuite is not only mineralogically valuable in its own right as a new mineral, but also provides a fresh perspective on jadeitite. In terms of crystallography, amaterasuite offers an important real-world example of the bridging of theory and observation. Its discovery is thus of great significance on many scientific fields.
Amaterasuite has a dual nature in which two types (A and B) are encapsulated in a unit cell. If one type is present, the other is absent. Like tossing a coin, if one aspect is manifest, the other aspect is hidden.
The Naming Process
Amaterasuite is a new mineral discovered from within jadeitite, a representative stone of Japan. It has a distinctive crystal structure that demonstrates a dual nature. These backgrounds informed the deliberations on naming the mineral.
Ultimately the name of Amaterasu Omikami emerged as the candidate. Amaterasu Omikami is a symbol of Japan, matching the symbolism of jadeitite as a representative stone of Japan. Moreover, the dual nature of Amaterasu, who is both a wild spirit (ara-mitama) and a gentle spilit (nigi-mitama), is an apt metaphor for the duality of the mineral’s crystal structure. Taking these elements into consideration as a whole, and to honor the stone culture of Japan, the mineral was named amaterasuite. This name was also officially approved by IMA-CNMNC.
About the Presenters/Researchers
Daisuke Nishio-Hamane, Technical Specialist
Institute for Solid State Physics, University of Tokyo
Mariko Nagashima, Young Advanced Professor
Graduate School of Science and Technology for Innovation, Yamaguchi University
Yuki Mori, Researcher
JASRI
Norimasa Shimobayashi, Professor
Graduate School of Science, Kyoto University
Takashi Matsumoto, Group Manager
Life Science Group, Application Lab
Rigaku Corporation
Masayuki Ohnishi
Mitsuo Tanabe
Amateur mineralogists
About the Thesis
Journal: Journal of Mineralogical and Petrological Sciences
Title: Amaterasuite, Sr4Ti6Si4O23(OH)Cl, a new mineral from jadeitite, a representative stone of Japan
Authors: Daisuke Nishio-Hamane*, Mariko Nagashima, Yuki Mori, Masayuki Ohnishi, Norimasa Shimobayashi, Takashi Matsumoto, Mitsuo Tanabe
(*corresponding author)
DOI: 10.2465/jmps.250420
URL: https://doi.org/10.2465/jmps.250420
Research Assistance
This research project was supported by use of joint research equipment of the Program to Promote Joint Use of Advanced Research Platforms of the Ministry of Education, Culture, Sports, Science and Technology (case number JPMXS0440400024) and a grant from the Japan Society for the Promotion of Science (case number 23K03551; representative: Mariko Nagashima).
Explanation of Terms
1 New mineral
Before submitting a paper on a new mineral, review and approval by the Commission on New Minerals, Nomenclature, and Classification of the International Mineralogical Association (IMA-CNMNC) are required.
2 Subduction zone
The location where two tectonic plates collide and one plate slides under the other. In this context, it refers to a place where an oceanic plate subducts beneath a continental plate.
3 A representative stone of Japan
In 2016 JAMS designated jadeitite as a representative stone of Japan, citing its status as a beautiful stone produced in Japan and its importance not only in mineralogy but in a wide range of other fields as well.
4 Rengeite and matsubaraite
Both rengeite and matsubaraite are new minerals discovered from within jadeitite produced in Itoigawa. Rengeite is named after Renge Mountain area, a mountain near the rengeite producing region, while matsubaraite is named after Satoshi Matsubara, a mineralogist.
5 SPring-8 large-scale synchrotron radiation facility
SPring-8 is a large-scale synchrotron radiation facility owned by the Institute of Physical and Chemical Research (RIKEN) in Harima Science Garden City, Hyogo Prefecture. The facility boasts the world’s highest performance in terms of synchrotron radiation generation. Support for users of SPring-8 is provided by JASRI. The name “SPring-8” stands for “Super Photon ring, 8 GeV.” At SPring-8, synchrotron radiation is used in a wide range of research fields, including nanotechnology, biotechnology and industrial applications.