大沢山温泉
O-sawayama Onsen塩
Chloride
+ Bicarbonate
- Color
- colorless and transparent
- Taste
- slightly salty
- Odor
- faint hydrogen sulfide
Sodium Chloride-Bicarbonate spring
Cold mineral source · 27°CCold mineralHigh silica
Composition fingerprint1.0 g/kg dissolved · Hypotonic
Na⁺98
Cl⁻72
HCO₃⁻26
◀ 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
- Smooth skindry, rough skin
- Cutsminor wounds
A cold-mineral spring (under 25 °C) drawn from the hills of Uonuma, Niigata, reheated for bathing. A sodium-led chloride water layered with a softening bicarbonate sub-type — weakly alkaline, with a faint salt tang on the lips and a trace of rotten-egg note from H₂S. The metasilicic acid content (82.7 mg/kg) leaves the skin noticeably smooth.
Sampled at wellhead·Analyzed Jul 8, 2025·一般社団法人 新潟県環境分析センター
