河原の湯
Kawara-no-yu SpringOperated by · 河原の湯組合
塩
Chloride
+ Sulfate
- Color
- colorless and transparent, with slight brown floating matter
- Taste
- not recorded
- Odor
- not recorded
Sodium-Calcium Chloride-Sulfate spring
pH 6.5NeutralHot source · 64°CHigh silica
Composition fingerprint2.0 g/kg dissolved · Hypotonic
Na⁺69
Ca²⁺25
Cl⁻67
SO₄²⁻30
◀ 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 — the Kawara-no-yu source of Shima Onsen in Nakanojo, Gunma — with sulfate close behind as a second anion, adding quiet body to the water. Neutral in pH and hypotonic, it feels soft rather than sharp, while roughly 2.0 g/kg of dissolved solids gives it genuine mineral weight and good heat retention. Metasilicic acid at 142 mg/kg places it squarely in Japan's beauty-water family, leaving the kind of silica film that makes skin feel noticeably smoother. At the wellhead the water is colorless and clear apart from a few faint brown flecks in suspension.
Sampled at wellhead·Analyzed Sep 12, 2007·社団法人 群馬県薬剤師会（環境衛生試験センター）