Magnesium bath flakes, sometimes called magnesium bath salts, are a highly concentrated form of magnesium supplementation, designed to be added to a bath or footbath. Soaking in a magnesium-rich bath helps promote relaxation and soothe tired and aching muscles. Allowing full body exposure to a concentrated solution of magnesium chloride. A gentle and effective method of supplementation. The magnesium used within Magnesium Flakes has been naturally purified over 250 million years to guarantee it is free from man-made pollutants and heavy metals.