鉄湯2号
Tetsuyu Spring No. 2酸
Acidic
+ 含硫黄泉 · Sulfate
- Color
- colorless and transparent, with white floating particles
- Taste
- not recorded
- Odor
- hydrogen sulfide odor present
Magnesium-Sodium-Hydrogen Sulfate spring
pH 2.4AcidicHot source · 85°CUltra-acidicSulfur-richHigh silica
Composition fingerprint1.4 g/kg dissolved · Hypotonic
Mg²⁺39
Na⁺27
H⁺20
SO₄²⁻79
Cl⁻15
◀ CationsAnions ▶
- Magnesium Mg²⁺
- mild; a laxative if you drink it.
- Sulfate SO₄²⁻
- "gypsum / Glauber's salt" — vessels and wound healing.
Known good for
- Skin conditionsatopic skin, eczema
- Circulationtired legs
- Aches & jointsstiff shoulders
- Sensitive-skin cautionbroken or dry skin
An acidic, sulfur-bearing spring at Manza: pH 2.4, sharp enough to prickle on the skin, with magnesium and sodium leading a sulfate-dominated water of moderate mineralization. At the wellhead it runs colorless and clear but carries white floating flecks and an unmistakable rotten-egg note of hydrogen sulfide. It is among Japan's hottest natural sources, and the posted analysis states plainly that water may be added so the bath is comfortable to enter. Metasilicic acid at 118 mg/kg leaves a thin silica film, and the bathing indications lead with chronic skin conditions and cuts, the classic territory for strongly acidic sulfur water.
Sampled at wellhead·Analyzed Mar 7, 2007·(社)群馬県薬剤師会 環境衛生試験センター
