Why Are There Rust Spots on My Corelle Dishes From the Dishwasher?

Corelle dishes have been a mainstay in American kitchens since 1970, when Corning Glass Works developed a new way to make glass dishes. The plates, bowls, mugs and serving pieces are inexpensive and readily available in many cheerful patterns to match any kitchen decor. These durable dishes are functional enough for everyday use and look good enough to set on the table for guests.

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Use care when loading your dishwasher to avoid rust spots.

Causes

Occasionally rust spots will appear on Corelle dishes. While there is no metal on the dish itself, rust typically shows up when the dish comes in contact with a metal object in the dishwasher--whether a rusted metal cookie sheet, utensil or even a rusted dishwasher rack. If no rusted items are making contact with the dish, yet spots are still appearing, confirm if any metal items are in the upper dishwasher rack or if a rust spot is on the roof of the dishwasher. Either of these can drip water down on dishes during the dry cycle and transfer the rust.

Commercial Solutions

You can remove nearly all rust spots on Corelle dishes with a moistened nylon or plastic cleaning pad and a non-abrasive cleaner. Corelle sells a liquid conditioning gel intended for removing rust spots and metal scratches from silverware, although other liquids and powders are available that can provide the same results. Test the cleanser on a small, inconspicuous area of a dish before applying it to the entire piece.

Natural Solutions

Natural ways of cleaning rust spots from Corelle dishes include sprinkling baking soda on the rust and using a moistened nylon or plastic pad to create a paste. Let the spot set for 30 minutes before rinsing it off.

Considerations

Don't use metal scouring pads or abrasive cleaners to remove rust spots on Corelle dishes; doing so will likely scratch the finish of the glaze and damage the integrity of the dish, inviting future breakage. Plate and bowl edges can become rough and porous over time because of hard water in the dishwasher. If rust appears on a rough edge, it will be extremely difficult to remove and may not come off at all.