It shows a deep ultramarine color.
Provided by the National Museum of Nature and Science
Lapis lazuli, known as Ruri in Japanese, has been loved since ancient times as a beautiful blue gemstone. The National Museum of Nature and Science announced that this stone has been found in Japan for the first time, where it was discovered along a tributary of the Hime River in Itoigawa City, Niigata Prefecture. Sources of this stone are very limited worldwide. The museum stated, "It may have been overlooked until now, and we expect more discoveries in the future."
Lapis lazuli is a rock made up of several minerals, such as hauyne and sodalite. Since ancient times, the only source for gem-quality stones was northeastern Afghanistan, and it was not known to exist in Japan. The museum performed chemical composition and X-ray tests on items that two hobbyists (both now deceased) had collected for fun which proved the stones were lapis lazuli, and the findings were announced on the 27th of last month.
Small pieces of lapis lazuli had been picked up on the city's beaches before, but people assumed they were foreign stones scattered during local events. Also, a similar-looking blue stone called "dumortierite" is often found in the riverbeds and on the coast. The museum suggested, "There might be lapis lazuli hidden in the collections of people who think they own blue stones that are just dumortierite."
Original article was provided by the Science Portal and has been translated by Science Japan.