Hard water

The hardness of the water results in a calcification

Hard water is water that has a high mineral content (contrast with soft water).

The main components of these minerals usually are calcium (Ca²⁺) and magnesium (Mg²⁺) ions. But there are also dissolved metals, bicarbonates, and sulfates. Calcium usually enters the water as either calcium carbonate (CaCO₃) in the form of limestone and chalk, or calcium sulfate (CaSO₄) in the form of several other mineral deposits. The main source of magnesium is dolomite (CaMg(CO₃)₂). Hard water is generally not harmful and some hardness in water is a useful source of calcium for healthy bone development .

Hard Water Media

A bathtub faucet with built-up calcification from hard water in Southern Arizona.
A portion of the ancient Roman Eifel Aqueduct in Germany. After being in service for about 180 years, the aqueduct had mineral deposits of up to 20 cm (8 in) thick along the walls.

Other websites

Alcoa Chemical, Langelier Saturation Index (LSI) Calculator Archived 2007-12-01 at the Wayback Machine

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