High quality mineral salt tablets for cleaning the water softening system. Produced with 99.8% pure Volterra Salt and absolutely free of any insoluble substance The Salt of Volterra is a recrystallized type of salt. The underground deposits are flooded with fresh water, that disolves the salt, it transforms it self in a concentrated saline solution at 33%, it is then purified at 80 degrees celsius to eliminate all the impurities that may contaminate it. The purified solution is thus sent to the crystallizers 40 meters high, where the high temperatures obtained from the vapor compression, bring the solution to130 degrees celsius, this evaporating the water present in the solution, leaving just the salt. This process is called Recrystallization of the salt, the wet salt is dried then sent for packaging in different types, designed to meet all market needs.