True Himalayan lamps are actually solid blocks of hand-carved Himalayan salt. The deep underground mines of Khewra , Pakistan, located on the western border of the Himalayas, are the only source of pink salt that is indigenous to the Himalayas. The color of Himalayan salt lamps ranges from light pink to pinkish-orange due to the concentration of minerals. Inside the center of this block cavity is an electric lamp that emits light and heat. And a lamp isn't a lamp at all if it doesn't have a light or heat source inside. Beneath it is just a block of salt.
Salt attracts water molecules. Since the Himalayan salt lamp works by attracting water molecules, it also attracts water vapor, which carries air pollutants such as mold, bacteria, and allergens. Once the water vapor comes into contact with the salt lamp, the pollutants are thought to become trapped within the salt. Since the lamp is heated, the salt dries quickly and can continue the cycle of attracting water vapor and pollutants, then releasing water vapor into the air and trapping harmful pollutants.