旅館湯本荘 源泉
Ryokan Yumotoso SpringOperated by · 旅館湯本荘
- Aches & jointsstiff shoulders
- Smooth skindry, rough skin
- Recoveryfatigue, stress
The source at Ryokan Yumotoso in Kurokawa Onsen is classified as a simple iron spring of the sulfate sub-type — iron-rich water that oxidizes reddish-brown once it meets the air. The certificate's older name for it, "simple melanterite spring", describes the chemistry literally: iron paired with sulfate, which dominates the anion side. Dissolved solids are light and the water is only weakly acidic, so it feels gentle rather than sharp, yet iron runs to 35 mg/kg — well past the threshold at which a spring counts as iron-bearing at all. Metasilicic acid is generous too, leaving the thin silica film that makes skin feel noticeably smoother afterwards.
Analyzed Oct 15, 2014·株式会社同仁グローバル