Every time the sea water evaporates, gypsum is deposited beside chlorine sodium; in the salt lakes, gypsum is first deposited, then the rock salt. In the canals of the salinas, it is often deposited in beautiful crystals and their passages are dropped. Sometimes in gypsum settlements it is possible to find smaller rock masses, which in addition to the fact that gypsum is usually the most common with rock salt, is the best evidence that the rock salt and gypsum deposit came from the sea. Many gypsum colonies are the remnants of rock formations, from which the water has washed out rock rock and the gypsum is left behind.