笹の湯
Sasa-no-yu Spring硫
Sulfate
+ Chloride
- Color
- colorless and clear, with a faint iron taste
- Taste
- faintly iron-tinged with a bitter note
- Odor
- not recorded
Sodium-Calcium Sulfate-Chloride spring
pH 4.3Weakly acidic
Composition fingerprint1.1 g/kg dissolved · Hypotonic
Na⁺51
Ca²⁺37
SO₄²⁻52
Cl⁻47
◀ CationsAnions ▶
- Sodium Na⁺
- salt's cation — pairs with chloride to make the water salty.
- Sulfate SO₄²⁻
- "gypsum / Glauber's salt" — vessels and wound healing.
Known good for
- Aches & jointsstiff shoulders
- Circulationtired legs
- Warmingcold sensitivity
A hot sodium-calcium spring with a sulfate-led, chloride-layered composition (sulfate dominates the anion balance, chloride sits a close second). Weakly acidic at the wellhead (pH 4.3), the water carries a faint iron taste and a touch of bitterness. Sulfate gives the bath a settled, mineral-rich body, while a salty edge from chloride and 140 mg/kg of metasilicic acid round it out.
Sampled at wellhead·Analyzed Oct 30, 1998·長野県衛生公害研究所