Kumihama Onsen Kongou-sen
Analysis VerifiedThe Kumihama Onsen Kongou-sen, or "Mixed Spring," is a unique hot spring created by blending two different sources. A high-temperature 51.2°C source (Calcium/Sodium - Chloride/Sulfate spring) is combined with a 32.0°C low-temperature source (Sodium/Calcium - Chloride spring) to achieve the perfect bathing temperature without adding any cold water. This method allows for a 100% pure, free-flowing "gensen kakenagashi" experience, with no heating, dilution, circulation, or disinfection. The source was famously discovered by Rokuro Yamada, the founder of Osaka's iconic "Kuidaore" restaurant.
The bar length shows how abundant each component is compared to thresholds that make it "distinctive" (therapeutic spring standards, beauty spring criteria, etc.).
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.
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.
Chloride springs create a veil of salt on the skin, which helps retain body heat. It is recommended to rinse lightly with a shower after bathing to leave the minerals on your skin. Its high moisturizing effect is suitable for dry skin. Take breaks to avoid overheating during long soaks.
With a weakly alkaline pH of 7.9, this spring is expected to have a skin-smoothing effect. The main component, chloride ions (Cl⁻ 840.1 mg/kg), coats the skin and prevents moisture from evaporating after bathing. This creates a high moisturizing and heat-retaining effect, earning it the name "Atsu-no-yu" (hot water for warmth). It is especially recommended for those suffering from poor circulation or dry skin.
Please refrain from bathing if you have general contraindications for hot springs, such as being in an active phase of an illness or feeling extremely weak. The spring is relatively mild, but be cautious about bathing for too long.
※ See the analysis data below for detailed contraindications
ANALYSIS DATAView all analysis fields ▼
Source Info
- Source name
- 久美浜温泉 低温泉源
- Spring type
- ナトリウム・カルシウム－塩化物泉
- Old spring type name
- 食塩泉
- Source temperature
- 33℃
- pH
- 7.66
- Flow rate
- 89 L/min
- Flow type
- 動力揚湯
- Osmotic pressure
- 低張性
Analysis Document
- Analysis date
- 2017-07-27
- Analyst organization
- 一般社団法人京都微生物研究所
Cations
- Lithium ion Li⁺
- 0.00 mg/kg
- Sodium ion Na⁺
- 398 mg/kg
- Potassium ion K⁺
- 10.0 mg/kg
- Ammonium ion NH₄⁺
- 0.00 mg/kg
- Magnesium ion Mg²⁺
- 7.2 mg/kg
- Calcium ion Ca²⁺
- 244 mg/kg
- Aluminum ion Al³⁺
- 0.00 mg/kg
- Manganese ion Mn²⁺
- 0.20 mg/kg
- Iron(II) ion Fe²⁺
- 0.00 mg/kg
- Iron(III) ion Fe³⁺
- 0.00 mg/kg
- Strontium ion Sr²⁺
- 2.0 mg/kg
- Barium ion Ba²⁺
- 0.00 mg/kg
- Copper ion Cu²⁺
- 0.00 mg/kg
- Total cations
- 0.66 mg/kg
Anions
- Fluoride ion F⁻
- 2.0 mg/kg
- Chloride ion Cl⁻
- 840 mg/kg
- Hydroxide ion OH⁻
- 0.00 mg/kg
- Hydrogen sulfide ion HS⁻
- 0.00 mg/kg
- Sulfate ion SO₄²⁻
- 245 mg/kg
- Bicarbonate ion HCO₃⁻
- 89.1 mg/kg
- Carbonate ion CO₃²⁻
- 0.00 mg/kg
- Bromide ion Br⁻
- 3.4 mg/kg
- Sulfide ion S²⁻
- 0.00 mg/kg
- Total anions
- 1.2 mg/kg
Undissociated Components
- Metasilicic acid H₂SiO₃
- 30.6 mg/kg
- Metaboric acid HBO₂
- 1.6 mg/kg
- Total undissociated
- 0.03 mg/kg
Dissolved Gas
- Free carbon dioxide CO₂
- 0.00 mg/kg
- Free hydrogen sulfide H₂S
- 0.00 mg/kg
- Total dissolved gas
- 0.00 mg/kg
Totals
- Total dissolved substances
- 1.9 mg/kg
- Component total
- 1.9 mg/kg
- Evaporation residue
- 2.3 mg/kg
Usage
- Heating
- No
- Dilution
- No
- Recycle / Filter
- No
- Additives
- No
- Disinfection
- No
Indications & Contraindications
- Bathing indications
- Chronic pain or stiffness in muscles and joints (rheumatoid arthritis, osteoarthritis, lower back pain, neuralgia, frozen shoulder, bruises, sprains, etc. in chronic stages), Muscle stiffness due to motor paralysis, Poor circulation, Peripheral circulatory failure, Gastrointestinal dysfunction (stomach heaviness, intestinal gas, etc.), High blood pressure (mild), Impaired glucose tolerance (diabetes), Dyslipidemia, Mild asthma or emphysema, Hemorrhoid pain, Autonomic instability, Stress-related symptoms (insomnia, depression, etc.), Post-illness recovery, Fatigue recovery, Health promotion, Cuts and grazes, Xeroderma
- Contraindications
- Active stages of illness (especially with fever), active tuberculosis, advanced malignant tumors or severe anemia causing significant physical weakness, severe heart or lung disease causing shortness of breath with slight movement, severe kidney disease with swelling, gastrointestinal bleeding, visible bleeding, acute exacerbation of chronic illness
Drinking
- Drinkability
- Not drinkable
