ConcenTrace Trace Mineral Drops is a natural mineral concentrate that is so concentrated that 40 drops equals the mineral content of 1/2 cup of sea water with 99% of the sodium removed. This liquid mineral formula offers a wide spectrum of nutritional health benefits. Due to the purity and concentration of this product, it is naturally preserved and contains no bacterial growth. The minerals do not lose potency over time. Minor crystallization may occur, but this doesn't affect the quality of the product.