Every spring has its own mineral recipe, and bathers have sworn by them for centuries. Here’s the honest, hype-free version:
- Sulphur — the classic “eggy” smell. Traditionally linked to skin and joint relief; the smell is the price of admission.
- Silica — gives water that milky, silky feel (hello, Blue Lagoon). Lovely on skin; murder on hair — condition first.
- Calcium & magnesium — the Budapest-style waters. Associated with muscle relaxation; also what makes travertine terraces.
- Iron — turns water rusty-brown (Arima’s “gold” spring). Traditionally used for circulation and warmth.
- Carbonic acid — lightly fizzy water that feels cooler than it is; prized in Japanese “silver” springs.
None of this is medical advice — but a hot soak after a long hike needs no clinical trial to prove its worth.