熱の湯
Netsunoyu SpringOperated by · 熱の湯組合
塩
Chloride
+ Sulfate
- Color
- colorless and clear
- Taste
- no taste or odor
- Odor
- no taste or odor
Sodium-Calcium Chloride-Sulfate spring
pH 7.0NeutralHot source · 65°CHigh silica
Composition fingerprint1.2 g/kg dissolved · Hypotonic
Na⁺60
Ca²⁺33
Cl⁻52
SO₄²⁻45
◀ CationsAnions ▶
- Sodium Na⁺
- salt's cation — pairs with chloride to make the water salty.
- Chloride Cl⁻
- table-salt anion — coats the skin and holds heat in.
Known good for
- Warmingcold sensitivity
- Circulationtired legs
- Aches & jointsstiff shoulders
A sodium-calcium chloride spring drawn from the Jigokudani valley in Yamanouchi, with sulfate running almost as strong and lending the water a quiet mineral body. The pH is neutral and the mineralization moderate at roughly 1,170 mg/kg of dissolved solids — enough substance to feel in the water, with none of the sting a sharper spring would carry. What stands out is the silica: a generous 151.9 mg/kg of metasilicic acid puts this squarely in Japan's beauty-water family, leaving the thin film that makes skin feel noticeably smoother after a soak.
Sampled at wellhead·Analyzed Nov 29, 1986·長野県衛生公害研究所