中尾高原温泉組合1号泉
Nakao Kogen Onsen Cooperative Spring No. 1Operated by · 中尾高原温泉組合
- Color
- colorless and transparent
- Taste
- tasteless
- Odor
- a faint sulfur note
Sodium-Calcium Bicarbonate-Chloride spring
- Sodium Na⁺
- salt's cation — pairs with chloride to make the water salty.
- Bicarbonate HCO₃⁻
- "soda" — softens skin, leaves it smooth.
- Skin conditionsatopic skin, eczema
- Circulationtired legs
- Aches & jointsstiff shoulders
- Sensitive-skin cautionbroken or dry skin
A simple sulfur spring of the hydrogen-sulfide type, drawn on the Nakao Kogen plateau in the Okuhida hot-spring district. At 87.4 °C at the wellhead it ranks among Japan's hottest natural sources, and while the water itself is colorless, transparent and tasteless, it carries the characteristic faint rotten-egg note of H₂S — 2.0 mg/kg of free hydrogen sulfide alongside a trace of bisulfide ion. Mineralization is light at 288 mg/kg of dissolved solids and the pH is neutral, so the feel on the skin is gentle rather than sharp. The certificate's sample was taken from the storage tank rather than at the wellhead.
Sampled at storage tank·Analyzed Nov 20, 2018·株式会社神岡衛生社·Cert no. No.18-P-11147
