Natural coral sand collected from the pristine seabed of subtropical Okinawa consists of reef-building corals and foraminifera, famously known as star sand. It contains high levels of approximately 20 essential minerals, including calcium and magnesium. When used as a water purification material, these minerals dissolve into the water, creating delicious mineral water with a natural balance. Simultaneously, coral sand shifts acidic drinking water toward a mildly alkaline state and removes chlorine odor from tap water. Its countless microscopic pores, smaller than 10 microns, enable the adsorption and removal of heavy metals and foreign substances.