Ocean UltraFine Swimming Pool Salt is a naturally evaporated sea salt (sodium chloride). Produced in Australia, this high quality pool salt uses the natural elements of Australia’s pristine waters, clean air and sun. It is then harvested, double washed, dried, sized and packaged in accordance with a system that complies with ISO 9001. Ocean UltraFine Swimming Pool Salt is a translucent to white solid, with a texture of medium-fine granules. It has a mean particle size approximately 0.3 mm and the addition of anticaking agent (535).