Nanjoen Gensen
Analysis UnverifiedThis spring began welcoming bathers in 1964, when the Yamanami Highway opened, on a rise at the center of Kurokawa Onsen. Though light in dissolved minerals, its weakly acidic water at pH 3.7 carries iron, releasing a faint sulfur and metallic note from nearly clear water. It suits travelers who stroll the mountain hot-spring village and want a refreshing soak between baths.
The bar length shows how abundant each component is compared to thresholds that make it "distinctive" (therapeutic spring standards, beauty spring criteria, etc.).
A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.
A trace component with gentle antibacterial and anti-inflammatory action.
The aroma typical of sulfur springs, with circulatory and antibacterial effects.
Scores are calculated from mineral analysis data based on the Mineral Spring Analysis Guidelines (Ministry of Environment, Japan). They are unrelated to facility atmosphere or service quality.
▸Note
The temperature, pH and component values shown here are based on the hot spring analysis (source). Actual values in the bath may differ depending on heating, dilution, recycling and filtration. Please check current usage status at the facility.
At pH 3.7 the weakly acidic water can feel slightly sharp, so rinse briefly with fresh water afterward. The 55.0°C source makes some tubs hotter than others; start in the cooler ones and work up.
With 169.9 mg/kg of metasilicic acid, this weakly acidic water leaves skin feeling fresh and may help it turn silky. As a gentle simple spring, it is traditionally associated with deep relaxation amid the quiet of Kurokawa's mountain valley.
Because the water is weakly acidic, those with sensitive skin should avoid long soaks and rinse afterward. People with general contraindications for hot-spring bathing should refrain.
※ See the analysis data below for detailed contraindications
ANALYSIS DATAView all analysis fields ▼
Source Info
- Source name
- Nanjoen Gensen
- Spring type
- Simple Hot Spring
- Source temperature
- 55℃
- pH
- 3.7
- Flow type
- 掘削動力揚湯
- Osmotic pressure
- 低張性
Analysis Document
- Analysis date
- 2022-09-06
- Analyst organization
- 株式会社三井テクノス
Cations
- Hydrogen ion H⁺
- 0.20 mg/kg
- Lithium ion Li⁺
- 0.50 mg/kg
- Sodium ion Na⁺
- 65.0 mg/kg
- Potassium ion K⁺
- 22.3 mg/kg
- Ammonium ion NH₄⁺
- 0.30 mg/kg
- Magnesium ion Mg²⁺
- 4.9 mg/kg
- Calcium ion Ca²⁺
- 22.3 mg/kg
- Aluminum ion Al³⁺
- 2.4 mg/kg
- Manganese ion Mn²⁺
- 0.40 mg/kg
- Iron(II) ion Fe²⁺
- 13.3 mg/kg
- Zinc ion Zn²⁺
- 0.40 mg/kg
- Lead ion Pb²⁺
- < 0.01 mg/kg
- Copper ion Cu²⁺
- < 0.01 mg/kg
- Total cations
- 0.13 mg/kg
Anions
- Fluoride ion F⁻
- 1.0 mg/kg
- Chloride ion Cl⁻
- 56.2 mg/kg
- Sulfate ion SO₄²⁻
- 204 mg/kg
- Bromide ion Br⁻
- 0.20 mg/kg
- Hydrogen sulfate HSO₄⁻
- 1.2 mg/kg
- Total anions
- 0.26 mg/kg
Undissociated Components
- Arsenious acid HAsO₂
- 0.70 mg/kg
- Metasilicic acid H₂SiO₃
- 170 mg/kg
- Metaboric acid HBO₂
- 3.6 mg/kg
- Total undissociated
- 0.17 mg/kg
Dissolved Gas
- Free carbon dioxide CO₂
- 149 mg/kg
- Free hydrogen sulfide H₂S
- 0.60 mg/kg
- Total dissolved gas
- 0.15 mg/kg
Trace Components
- Radon Rn
- 0.06 mE/kg
Totals
- Total dissolved substances
- 0.57 mg/kg
- Component total
- 0.72 mg/kg
Usage
- Usage status
- Unknown
Indications & Contraindications
- Bathing indications
- Autonomic instability, Insomnia, Depression
- General indications
- High blood pressure (mild), Rheumatoid arthritis, Chronic pain or stiffness in muscles and joints, Muscle stiffness due to motor paralysis, Gastrointestinal dysfunction
- Contraindications
- Acute illness (especially with fever), Active tuberculosis, Malignant tumors, Severe heart disease, Respiratory failure, Renal failure, Bleeding disorders, Severe anemia, Any actively progressing illness, Pregnancy (especially early and late stages)
Drinking
- Drinkability
- Not drinkable
