Ancient Minerals magnesium flakes are dry flakes of magnesium chloride hexahydrate and other trace minerals, in a convenient and economical form for utilization in baths and foot soaks. Ancient Minerals magnesium flakes are approximately 47% magnesium chloride by weight. Where Do Ancient Minerals Magnesium Bath Flakes Come From? Ancient Minerals magnesium flakes are extracted from the Ancient Zechstein Seabed in Europe, 1600 to 2000 meters deep in the interior of the Earth. Well protected for the last 250 million years, they are the most pure magnesium flakes in the world and a mark of purity on every bottle of Ancient Minerals. Please visit www.ancient-minerals.com, for more detailed information on the Ancient Minerals brand of ultra pure topical magnesium products, including magnesium oil,magnesium gel, magnesium bath flakes, and magnesium lotion.