If rust develops around the rim, it may be that the pan has been in a damp area. Leaving pans on a draining board to drip dry or cleaning in the dishwasher can cause a rust deposit. Rust can also form if the rim of the pan is not dried sufficiently after being washed. Should rust develop, we recommend cleaning with a nylon sponge and dish detergent and dry thoroughly. We recommend rubbing a small amount of cooking oil around the rim to create a seal and prevent rust from re-appearing. We recommend rubbing with oil periodically to prevent rusting.