Soothing SOLUTION - Marine Crystals (Apple Cider Vinegar & Ginger) are soaking salts that we mainly use in cases of yeast or itchy feet. Apple cider vinegar contains more than 30 nutrients: minerals, vitamins and essential acids, several enzymes and a good dose of pectin. It is particularly rich in potassium and other trace elements such as phosphorus, calcium, magnesium, sulfur, iron, fluorine, silicon, boron and many more.