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Since the lamp is made of salt, it will absorb water and may start melting if it is placed in areas of near sources of water. Keep the lamp in dry places. Don’t place it near showers, bathtubs, dishwashers, or washing machines. Extra humidity in your home may cause the salt lamp to melt. To help with this, you may want to use a dehumidifier in your home to reduce the moisture in the air. This may be especially important if you live in a humid climate. Since humidity is the main thing that melts a salt crystal lamp, you may want to put the lamp away into a dry closet or room when using anything that creates steam. For example, you may want to move it somewhere different if you are boiling water on the stove, taking a shower, or washing laundry. Make it a habit to wipe down your lamp to remove excess moisture. Use a cloth, towel, or other item that won’t leave lint behind on the lamp. If you don’t want to do this every few days, wait until you notice moisture on the lamp.

Summary:
Place the lamp in a dry area. Reduce the humidity in your home. Put the lamp away when using appliances that create steam. Dry the lamp often.