Gypsum crust on the bottom of an evaporation pond in Eilat, Israel,
at a salinity of about 200 g/l.
Salterns are generally operated as a series of ponds of increasing salinity, so that different salts precipitate in different ponds. Long before NaCl (halite) precipitates, gypsum (CaSO4 . 2 H2O) is formed.
Saline Microsafari
