The iron in the cast iron skillet actually leaches into your food and adds the mineral to your diet. Cast iron skillets will last a long time if you take care of them properly. Once rust forms on the cast iron skillet, it needs to be removed to keep the skillet in good condition. Instead of throwing away your cast iron skillet, you can clean and season it to keep the skillet in your kitchen collection.
Scrub the cast iron skillet with a non-metallic scrubber and warm water. Scrub on the cast iron skillet until you remove most of the rust.
Rinse the skillet with warm water. Continue to scrub on the rust until you remove it completely from the skillet.
Wash the skillet with a mild dish soap and warm water. Rinse the skillet off and dry it with a clean towel.
Re-season the cast iron skillet after you remove the rust. When you scrub the skillet, it removes the seasoning necessary to cook food properly and keep it from sticking to the skillet. Brush vegetable shortening on the skillet, and work the oil in with a paper towel. Move the paper towel in a circular motion to ensure that the shortening sticks to the skillet.
Turn the skillet upside down on a sheet of aluminum foil in the oven. Bake the cast iron skillet in the oven at 350 degrees for one hour. Wipe the skillet off with a paper towel.
Allow the skillet to cool completely. Clean it with oil and salt instead of dish soap; this will protect the seasoning. Store the cast iron skillet with a paper plate between the pans to absorb any excess moisture.