While balneology is CONSIDERED DISTINCT from hydrotherapy, there are SOME overlaps in underlying principles and practice. Balneotherapy may involve the use of hot or cold water, massage done through moving water and for relaxation or stimulation purposes. Mineral waters at spas are rich in particular minerals such as silica, sulfur, selenium, and radium and are highly therapeutic. 'Fangotherapy', which uses medicinal clays, are also widely used for therapy.

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