Bromide Ion (Br⁻) Analysis · Deep Relaxation & Chloride Springs

Table of Contents

What is Bromide ion?
Main Effects
Bromide ion Top 5 Hot Springs

What is Bromide ion?

Bromide ion (Br⁻) is found alongside chloride in sea-derived springs. It is said to be absorbed through the skin and calm nervous tension.

Main Effects

Said to calm nervous tension
Deep relaxation after bathingThe sedative action of bromide ions is said to help shift the body toward a state of rest, inducing a profound sense of calm. This effect often lingers well after you leave the bath, contributing to a lasting feeling of deep, full-body relaxation.
Often coexists with chlorideBromide ions are a key indicator of seawater-derived hot springs. As such, they are almost always found alongside chloride and iodide ions, which are also abundant in seawater and contribute to the water's characteristic heat-retaining properties.

Bromide ion Top 5 Hot Springs

Top 5 hot springs registered on this site with the highest content.

RANKING BY THIS MINERAL CONTENT

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References

SPRING TYPEMay 5, 2026· 1min read

Iodine-Containing Springs: A Non-Volcanic Rarity & Its Drinking Indication

Iodine-containing springs hold iodide ions (I⁻) at 10 mg/kg or more, mainly found in non-volcanic geological strata. Clear at first, they turn yellow when left to stand. Drinking is indicated for dyslipidemia. Note: persons with hyperthyroidism should be cautious.

MINERALMay 5, 2026· 1min read

Iodide ion: Main Effects & Top 5

Iodide ion (I⁻) at ≥ 10 mg/kg classifies the spring as an "iodine spring." Common in non-volcanic springs, it is said to have antibacterial action, and high cholesterol is listed as a drinking indication.

MINERALMay 5, 2026· 2min read

Metasilicic Acid: The "Beauty Spring" Standard Mineral & Top 5 Onsen

Metasilicic acid (H₂SiO₃) is a natural moisturizer also found in skincare lotions. Hot springs containing more than 50mg/kg are called "beauty springs" — leaving skin hydrated long after bathing. This is one of the therapeutic spring criteria in Japan's Mineral Spring Analysis Guideline (Table 1-1).

Bromide ion: Main Effects & Top 5