Mineral waters are those that contain some dissolved minerals in sufficient concentration to change the taste or perceived health effects of the water. Mineral water originates as groundwater and flows along the local groundwater gradient, dissolving available geologic material until it reaches the surface as a spring, or until the water is pumped to the surface from a well.
The chemical and physical characteristics of mineral water depend on the nature of the geologic materials through which the groundwater has moved. Common soluble minerals include calcium carbonate, iron compounds, sodium and magnesium salts, sulfur compounds, and metals.
Mineral waters are usually classified as alkaline, saline, ferrous, sulfurous, acidulous, or soda, and may be either cold (down to about 4.5°C or 40°F) or hot (up to about 100°C or 212°F). Some mineral waters may originate from deep within the Earth, being heated by geothermal sources of either volcanic or tectonic nature. Hotter water typically dissolves more materials, making the mineral concentration higher.
Mineral water has been sought after for various health-related benefits since ancient times. Soda (naturally carbonated) waters have been used as table beverages and to dilute spirits or wines. Saline waters are typically ingested for their perceived medicinal effects.
Mineral water used for bathing can be enjoyed by complete submersion, or by wrapping the body in wet sheets or towels. Baths at skin temperature (about 37°C or 98.6°F) are relaxing. The hot bath stimulates, relieves pain (particularly of cramps and sometimes of arthritis), controls convulsions, and induces sleep. Quickening the pulse and respiration, it also increases perspiration, thereby relieving the kidneys of part of their
Although thousands of people suffering a variety of ailments frequent mineral baths in search of the cures attributed to local waters and mud, physicians generally doubt their medical value. Among the most popular medicinal baths are those in which the waters of natural warm mineral springs can be found. Resorts, sometimes called spas, have grown up near such springs.
Spas, by definition, are located where natural sources of mineralized water are used for drinking or bathing to enhance good health. The term "spa" was named after Spa, a town in eastern Belgium, which is a popular resort known for its baths and mineral springs. The waters have been frequented since ancient times. Such spas remain popular worldwide.
and Kari Salis
Ahman, Nathaniel. Healing Springs: The Ultimate Guide to Taking the Waters, Rochester, VT: Healing Arts Press, 2000.
Hem, John D. Study and Interpretation of the Chemical Characteristics of Natural Water, 3rd ed. Alexandria, VA: U.S. Geological Survey, Water-Supply Paper W2254 (1985).
Mineral springs with significant flows can be found in Saratoga, New York; Berkeley Springs, Virginia; and White Sulfur Springs, West Virginia. Well-known springs are also located in Kentucky, Tennessee, Arkansas, Indiana, Wisconsin, Nevada, New Mexico, California, and Washington. Many smaller or lesser-known mineral springs and spas can be found throughout the country.