Crystal salt lamps can emit natural negative ions, especially fully when heated, which can effectively balance the content of positive and negative ions in the air, equivalent to an air purifier.

The German Biophysical Institute has revealed the air purification principle of salt lamps. The main ingredient of crystal salt is sodium salt. Salt lamps absorb moisture from the air, then evaporate, and then absorb, then evaporate, alternately repeatedly, and continuously produce negative ions in this process. Heated salt lamps absorb water molecules in the surrounding air to the surface, and when salt and water molecules mix, they will dissolve after the water molecules evaporate, and Na+ and Cl- return to a neutral state. The water molecules evaporated carry negative ions generated by the ionization of water molecules, so the air is purified by this continuous reaction. This unique ion generation process is only found in crystal salt mines, because the electrically neutral atomic structure of salt mines determines that salt mines have the ability to generate negative ions when water is present.

According to expert statistics, salt lamps can increase the number of negative ions in each cubic centimeter of air by 500-700, making them particularly suitable for placing next to electronic devices such as computers and televisions to neutralize positive ions and shield harmful electromagnetic radiation from these devices.