Celtic sea salt, also commonly known as Sel gris or gray salt in French, is harvested from seawater. As the tide comes in, Seawater is first allowed to settle in clay silt ponds where the combined effects of wind and sun form a dense brine.
Celtic sea salt is different from regular table salt because it is not refined or processed, and thus retains more natural trace elements such as magnesium, potassium, and calcium.