ほたるの宿 仙洞
Sendou Firefly InnOperated by · 有限会社 湯布院インテック
湯
Simple
- Color
- colorless and clear
- Taste
- tasteless
- Odor
- odorless
Sodium Bicarbonate-Chloride spring
pH 8.3Weakly alkalineHot source · 57°CHigh silica
Composition fingerprint0.7 g/kg dissolved · Hypotonic
Na⁺81
HCO₃⁻40
Cl⁻31
SO₄²⁻17
◀ CationsAnions ▶
- Sodium Na⁺
- salt's cation — pairs with chloride to make the water salty.
- Bicarbonate HCO₃⁻
- "soda" — softens skin, leaves it smooth.
Known good for
- Aches & jointsstiff shoulders
- Smooth skindry, rough skin
- Recoveryfatigue, stress
A simple thermal spring rising in Yufuin. Sodium and bicarbonate lead the ion table, but with only about 0.7 g/kg of dissolved solids the water stays lightly mineralized and gentle on the body. It is mildly alkaline and soft on the skin, and a generous 198 mg/kg of metasilicic acid puts it in Japan's beauty-water family — the silica leaves a thin film that makes skin feel noticeably smoother once you are out.
Sampled at wellhead·Analyzed Sep 11, 2012·公益社団法人大分県薬剤師会·Cert no. 大薬検 第7R-24090005号