When you see a clear hot spring, do you think, "Isn't it low in minerals?" This is a big misconception. Many clear hot springs are rich in minerals and offer excellent benefits. Don't judge a hot spring's value by its appearance.

What is a Clear Hot Spring?

A clear hot spring refers to a colorless, transparent hot spring without any cloudiness. In fact, most hot springs in Japan are clear.

Because milky or colored hot springs stand out, many people have the image that "hot springs = cloudy." However, in reality, clear hot springs are far more common.

Why Are They Clear?

Hot springs are clear because the minerals are completely dissolved in the water.

There are no particles like sulfur floating around. There are no minerals like iron that oxidize and precipitate when exposed to air. When these conditions are met, the hot spring becomes clear.

Clear does not mean low in minerals; it simply means the minerals are completely dissolved.

Types of Clear Hot Springs

Japan's clear hot springs span various types of mineral compositions.

Simple Hot Springs: The most common type in Japan. Most are clear.

Chloride Springs: Contain salt derived from seawater, ranging from clear to yellowish-brown. Many are clear.

Sulfate Springs: Visually indistinguishable from simple hot springs in terms of clarity.

Bicarbonate Springs: Many are clear, though some can be milky.

Radioactive Springs (Radon Springs): Completely clear and visually indistinguishable from other hot springs.

Iodine Springs: Range from clear to yellowish-brown. Many are clear.

The Appeal of Clear Hot Springs

Clear hot springs have their own unique appeal.

Sense of Security: You can see the bottom, making it safe for your feet. Less slippery.

Sense of Cleanliness: Visually feels clean, meeting the Japanese preference for "cleanliness."

Gentle on the Skin: Many have low-irritation mineral compositions, making them safe for sensitive skin.

Suitable for Long Baths: Low irritation allows for leisurely soaking.

Easy for Drinking: Many clear hot springs are suitable for drinking (onsen drinking).

Hot Springs with "Invisible Benefits"

Among clear hot springs, some have "invisible benefits."

Radioactive springs (radon springs) are a prime example. They are completely clear and odorless, yet contain trace amounts of radon, which is believed to have health benefits.

Iodine springs are often clear as well. They contain iodine, which is expected to be effective for hypercholesterolemia.

While you can't see it, the minerals are definitely there. This is the intriguing aspect of clear hot springs.

Notable Clear Hot Springs

Gero Onsen (Gifu Prefecture): One of Japan's three famous hot springs. An alkaline simple hot spring known for its clarity and reputation as a "beauty bath."

Hakone Onsen (Kanagawa Prefecture): Offers various types of hot springs, many of which are clear.

Arima Onsen's Gin-sen (Hyogo Prefecture): Clear carbonated and radium springs. Called "Gin-sen" in contrast to the "Kin-sen" (reddish-brown).

Misasa Onsen (Tottori Prefecture): Boasts one of the world's highest radon contents, yet is completely clear.

Which is Better: Clear or Cloudy Hot Springs?

This is a common question. The answer is, "Both are good."

The value of a hot spring is not determined by its appearance. A combination of factors such as mineral composition, pH value, temperature, and benefits determine a hot spring's characteristics.

Clear hot springs are low in irritation and suitable for long baths. Cloudy hot springs offer strong visual impact and a sense of "authentic hot spring" experience.

Which is better depends on personal preference. Enjoy both.

Check the Hot Spring Analysis Sheet

When visiting a clear hot spring, it's recommended to check the hot spring analysis sheet.

The analysis sheet lists the mineral composition, pH value, main components, and benefits. Even clear hot springs contain various minerals.

You might discover that "it looks clear, but it's actually a chloride spring with excellent heat retention" or "it's clear, but alkaline with beauty benefits."

Conclusion

Clear hot springs are the most common type in Japan. Though they may seem plain, they are rich in minerals.

Clear means the minerals are completely dissolved. Some, like radioactive springs or iodine springs, have benefits not visible to the eye.

The value of a hot spring is not determined by its appearance. Both clear and cloudy hot springs have their own appeal. Enjoy both and savor Japan's diverse hot spring culture.