平山温泉 元湯
Hirayama Onsen Moto YuOperated by · 平山温泉・元湯 内風呂（女湯内湯）
湯
Simple
Sodium Carbonate-Bicarbonate spring
Hot source · 43°CStrongly alkalineHigh silicaHigh radon
Composition fingerprint0.3 g/kg dissolved · Hypotonic
Na⁺92
CO₃²⁻32
HCO₃⁻27
Cl⁻20
◀ CationsAnions ▶
- Sodium Na⁺
- salt's cation — pairs with chloride to make the water salty.
- Carbonate CO₃²⁻
- strongly alkaline; slippery feel.
Known good for
- Aches & jointsstiff shoulders
- Smooth skindry, rough skin
- Recoveryfatigue, stress
A sodium-led alkaline simple thermal spring. At pH 9.6 it is strongly alkaline, giving the pronounced slippery feel of Japan's beauty-water family. A hot source at 43.4 °C, it carries 59.3 mg/kg of metasilicic acid that leaves skin noticeably smoother, and enough radon to fall within the hormesis tradition.
Analyzed Mar 16, 2015·株式会社東洋環境分析センター