Himalayan salt lamps are made from pure, food grade, 250 million year old Himalayan salt crystals. 

These Lamps can be used as Air purifiers: Salt is hygroscopic, meaning it attracts water molecules from the surrounding air. A large block of rock salt, like a Himalayan salt crystal lamp, is especially attractive to water vapor and its attached pollutants. Once attracted to the lamp, these microscopic allergens remain on the salt and not floating in the air where you could previously breathe them into your lungs.

Not only will it help clean the air and expose you to at least some negative ions, it may also help counteract electromagnetic radiation.
 
Himalayan Salt Lamps can help: Reducing allergy and ashma symptoms, reducing stress, relieving headaches & migraines, have a better sleep...