鉄輪温泉泉管理組合
Kannawa Onsen Spring Management UnionOperated by · 鉄輪温泉泉管理組合
湯
Simple
- Color
- colorless, very faintly cloudy
- Taste
- very faintly sour
- Odor
- moderate hydrogen sulfide odor
Sodium-Calcium Sulfate-Chloride spring
pH 4.2Weakly acidicHot source · 70°CHigh silica
Composition fingerprint0.4 g/kg dissolved · Hypotonic
Na⁺49
Ca²⁺30
SO₄²⁻59
Cl⁻40
◀ 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
- Smooth skindry, rough skin
- Recoveryfatigue, stress
A weakly acidic, hypotonic simple thermal spring rising by natural flow from a bored well in the Oniyama district at a scalding 69.9 °C, placing it among Japan's hottest natural sources. The water is colorless and very faintly cloudy at the source, carrying the moderate rotten-egg note of hydrogen sulfide that marks the Kannawa field. It is unusually rich in metasilicic acid at 124 mg/kg, leaving the kind of thin silica film that makes skin feel noticeably smoother afterwards.
Sampled at mixing tank·Analyzed Sep 21, 2021·公益社団法人 大分県薬剤師会 大分県薬剤師会検査センター·Cert no. 大薬検 第7R-21090009号