Miharayama Onsen Well No. 5
Analysis UnverifiedMiharayama Onsen Well No. 5 draws groundwater heated by the still-active Mt. Mihara from roughly 300 m underground. Although it surfaces at over 84°C, its chemistry is gentle: clear, faintly bitter water that wraps the skin softly. Steeping here while gazing across the volcanic island's lava fields suits travelers who want to let the fatigue of a day of island hiking linger away.
The bar length shows how abundant each component is compared to thresholds that make it "distinctive" (therapeutic spring standards, beauty spring criteria, etc.).
A trace component with gentle antibacterial and anti-inflammatory action.
A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.
Absorbed through the skin to gently promote peripheral circulation.
Transdermal absorption gently supports skin hydration and muscle relaxation.
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.
As a neutral, low-irritation simple spring, it suits sensitive skin and older bathers. Because the source is very hot, check each bath's temperature, pour water over yourself first, and ease in slowly.
With a neutral pH of 6.9 and a mild total of 0.91 g/kg, this simple spring is easy on the body and invites deep relaxation. Containing 333.8 mg/kg of metasilicic acid, it is a gentle form of balneotherapy after a day exploring the island.
The source exceeds 84°C, so mind the water temperature. People with acute illnesses or serious heart conditions should avoid bathing.
※ See the analysis data below for detailed contraindications
ANALYSIS DATAView all analysis fields ▼
Source Info
- Source name
- Miharayama Onsen Well No. 5
- Spring type
- Simple Hot Spring
- Source temperature
- 84.2℃
- pH
- 6.9
- Flow rate
- 120 L/min
- Flow type
- 動力揚湯
- Osmotic pressure
- 低張性
Analysis Document
- Analysis date
- 2018-11-09
- Analyst organization
- 株式会社東京水質研究所
- Registration No.
- 19東京都温泉分析第2号
Cations
- Hydrogen ion H⁺
- < 0.1 mg/kg
- Sodium ion Na⁺
- 43.9 mg/kg
- Potassium ion K⁺
- 17.2 mg/kg
- Magnesium ion Mg²⁺
- 15.6 mg/kg
- Calcium ion Ca²⁺
- 56.6 mg/kg
- Aluminum ion Al³⁺
- < 0.1 mg/kg
- Manganese ion Mn²⁺
- 0.30 mg/kg
- Iron(II) ion Fe²⁺
- 0.10 mg/kg
- Iron(III) ion Fe³⁺
- < 0.1 mg/kg
- Zinc ion Zn²⁺
- 0.01 mg/kg
- Lead ion Pb²⁺
- < 0.01 mg/kg
- Copper ion Cu²⁺
- 0.00 mg/kg
- Cadmium ion Cd²⁺
- < 0.001 mg/kg
- Total cations
- 0.13 mg/kg
Anions
- Fluoride ion F⁻
- < 0.1 mg/kg
- Chloride ion Cl⁻
- 37.4 mg/kg
- Hydroxide ion OH⁻
- < 0.1 mg/kg
- Hydrogen sulfide ion HS⁻
- < 0.1 mg/kg
- Sulfate ion SO₄²⁻
- 38.1 mg/kg
- Bicarbonate ion HCO₃⁻
- 268 mg/kg
- Carbonate ion CO₃²⁻
- 0.20 mg/kg
- Hydrogen sulfate HSO₄⁻
- < 0.1 mg/kg
- Arsenite ion AsO₂⁻
- < 0.1 mg/kg
- Sulfide ion S²⁻
- < 0.1 mg/kg
- Total anions
- 0.34 mg/kg
Undissociated Components
- Sulfuric acid H₂SO₄
- < 0.1 mg/kg
- Arsenious acid HAsO₂
- < 0.1 mg/kg
- Metasilicic acid H₂SiO₃
- 334 mg/kg
- Metaboric acid HBO₂
- 38.5 mg/kg
- Total undissociated
- 0.37 mg/kg
Dissolved Gas
- Free carbon dioxide CO₂
- 56.5 mg/kg
- Free hydrogen sulfide H₂S
- < 0.1 mg/kg
- Total dissolved gas
- 0.06 mg/kg
Totals
- Total dissolved substances
- 0.85 mg/kg
- Component total
- 0.91 mg/kg
- Evaporation residue
- 0.69 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
