alkaline spring with H2 gas at Bahla, Oman

Surface waters associated with serpentinite bedrock in Oman are often alkaline (pH ≈ 9-12) and commonly emit contain flammable bubbles composed chiefly of natural hydrogen gas (H2). The Bahla Spring has been used since time immemorial for bathing and was once widely regarded as the lair of a genie.

Gordon Stanger, who has conducted the definitive study the unusual springs of Oman along with Colin Neal, notes that bathers often leave garments, food, or other items of value at the Bahla spring as offerings in exchange for a bath. So articles of clothing can be seen strewn about the ground next to the spring.