Jadeite is a rare rock which forms in subduction zones, where the massive tectonic plates covering our planet's surface plunge deep into the mantle. The Japanese archipelago sits atop such a subduction zone and jadeite deposits can be found across the country, but Itoigawa's jadeite stands unrivaled in its quantity and quality, being East Asia's only source of gemstone quality jade. Although lost and forgotten for centuries, jade is an invaluable part of Itoigawa's geological and cultural heritage.

In September 2016, the Japan Association of Mineralogical Sciences selected jadeite to be the National Stone of Japan. In 2022, the Niigata Prefectural Assembly voted to officially designate this beautiful stone as the Prefectural Stone of Niigata.