洞輪沢温泉
Borawazawa OnsenOperated by · 八丈町長 山下奉由
Sampled at bath inlet
曹
Bicarbonate
+ Chloride · Sulfate
Classification
Calcium-Sodium Bicarbonate-Chloride-Sulfate spring
A calcium-and-sodium-led bicarbonate spring layered with chloride and sulfate sub-types — the classic Japanese bicarbonate style, with a faintly salty edge and quiet sulfate body. Weakly alkaline and soft on the skin, it sits in the established beauty-water family. A generous 140.5 mg/kg of metasilicic acid leaves the kind of silica film that makes skin feel noticeably smoother afterwards. Sampled at the bath inlet rather than the wellhead.
pH
7.80
Weakly alkaline
Source temperature
41.2°C
Warm
Tonicity
1.30g/kg
Hypotonic
Flow rate
150L/min
Typical
Free CO₂
14mg/kg
Low
- Color
- colorless and transparent
- Taste
- tasteless
- Odor
- odorless
Highlights
- High silica
Analyzed Nov 4, 2015·公益財団法人 中央温泉研究所·Cert no. 甲第3618号