What is it
By chemical definition, a salt is a neutral ionic compound that forms crystals. There are hundreds of these kinds of compounds and the different salts used in human food are simply referred to as Salt. Salt has a density of 2.078 and has white crystals in the form of cubes grouped and joined together in a way that forms small dug pyramids with a square base (see image).
Salt can either come from the ocean or from mines.
The ocean water has an average of 35g of different salts per Kg of liquid. Of these 35g it is possible to find around 85 elements where sodium chloride is the most common with at least 89% of the total minerals.
Rock salt or mineral salt can be identified as sodium chloride in mines. Its origin is mainly due to the evaporation of large quantities of salty water thousands of years ago. It can also have a chemical origin through large quantities of thermal waters that emerged from the inside of the earth giving place for large quantities of rock salt.
Salt is the second most abundant chemical combination that exists on the surface of the earth, the first one being water. If all of the oceans around the globe would evaporate the height of the salt would be higher than 40 meters.