Salt of the Hayward Shoreline
Salt is gathered using two main methods: mining and solar evaporation.
The mining method is considered to be a form of deep-shaft mining where people dig for salt that already exists in ancient underground seabeds. When using this method, minders systematically blast through underground walls of salt and collect what has come from the previous walls. A good portion of what is collected using the mining method is produced as rock salt.
The solar evaporation method (this is how the Oliver Salt Company produced salt) is just as labor intensive and, quite possibly, more labor intensive. When using this method, ocean water is taken inland into marshes and put through different processes until we get salt—it’s a little more complicated than that so let’s start at the beginning. First, it is a relatively common misconception that salt is directly within ocean water but geologically speaking, only the ingredients for salt are mixed into the ocean. The sea gets matter from two main sources: 1) streams, rivers, runoff, and other water sources carry sodium ions from eroded rocks into the ocean and 2) oceanic volcanic activity provides chloride ions. Together, sodium ions and chloride ions are extremely compatible but H2O keeps the two separated. As H2O is eliminated through precipitation, sodium and chloride become one to make halite (technical term for salt). When salt is reintroduced to other elements, e.g. saliva from our tongues, the two minerals instantly dissolve into separates again.