内海・山海温泉 1号井
Utsumi-Sankai Onsen Well No. 1A sodium chloride strong-salt spring drawn from roughly 1,300 m below ground. The source emerges at 27.2 C and is heated for bathing, but the chemistry is anything but mild — hypertonic mineralization above ocean salinity leaves a thick mineral film on the skin long after the soak. Locally called a fossil-water spring and the chōju-no-yu (longevity spring), this is the sort of strongly mineralized chloride water traditionally invoked for nerve pain, muscle aches, and poor circulation.
- Strong salt
Analyzed May 7, 2013·株式会社環境科学研究所·Cert no. 愛知第2号