Salt is harvested from seawater through evaporation. The evaporation method depends on the geographical area and whether the saltwater is processed in large or small batches.
In drier areas, sea salt is harvested by exposing it to the sun and air in short-depth pools. If the air is too humid, the water will not evaporate as easily. Once all the water has evaporated, the salt is collected by harvesters. More often, seawater is processed commercially through vacuum pans, though the water is still evaporated away from the salt. In this process, it is evaporated by boiling the water off rather than through the heat of the sun, according to How Stuff Works.
In fact, homeowners can harvest salt at home if they live close to the ocean by letting the sand drift down out of it and pouring the water out. Then the homeowner pours the water into containers to evaporate in the sun. If it is especially humid, the salt can be finished in the oven at a very low temperature.
Seawater contains about 2.65 percent salt. The rest is mostly water, although it also contains small amounts of other compounds and elements such as carbon and fluoride. According to the Encyclopedia Britannica, the salts found in water include regular table salt (sodium chloride) as well as other salts, such as bromine, potassium and magnesium.