上湯温泉
Kamiyu OnsenKamiyu Onsen is a sodium-bicarbonate spring with a notable iron(II) signature — the jūsō-sen softness of an Na-HCO3 base, overlaid with the rusty character of dissolved iron that oxidizes reddish-brown on contact with air. The water emerges at 53.6 °C, classified as a hot spring, and reaches the bath at the same temperature without cooling. Weakly alkaline at pH 7.7, it carries the soft, skin-smoothing feel of the bicarbonate family alongside a metallic edge from the iron content.
- Iron-rich
Analyzed Sep 8, 2019