HIGH PURITY: Solar salt boasts a typical purity level of 99.6%, ensuring excellent quality. NATURAL CREATION: Crafted through the power of sun, wind, and time, solar salt is formed naturally. CRYSTAL APPEARANCE: Solar salt crystals possess a natural white and opaque appearance. LOW INSOLUBLE CONTENT: This type of salt contains minimal insoluble elements, enhancing its effectiveness. WIDE APPLICATION: Recommended for all water softeners, solar salt is NSF Certified to NSF/ANSI/CAN 60 standards. Diamond Crystal Solar Natural Water Softener Salt, 40 lb. These salt crystals are advertised as being produced using natural processes like sun, wind, and time. They claim to be about 99.6% pure and are intended for treating hard water. Hard water contains high levels of minerals like calcium and magnesium, which can cause scale buildup in pipes and appliances, reduce the effectiveness of soaps and detergents, and create other issues. Solar salt crystals are commonly used in water softeners to replace the calcium and magnesium ions in hard water with sodium ions, helping to prevent scale buildup and improve the quality of the water. The use of solar salt crystals is considered a more natural and environmentally friendly option compared to some other water softening methods that might involve chemicals. Diamond Crystal Solar Natural Solar Salt Crystals are white, opaque appearance and are recommended for use in all water softeners. It's important to follow the manufacturer's instructions and guidelines for proper usage in your water softening system.