Not Dishwasher Safe: Things You Should Never Put in the Machine

Acrylic

Adhesive-joined pieces

Aluminum, including anodized aluminum

Antiques

Blown glass

Brass

Bronze

Cast iron

China with metallic decoration

Crystal

Disposable plastics not labeled "dishwasher-safe"

Flatware with bone, plastic, or wood inlays or handles

Gold-plated flatware

Iron

Knives

Many nonstick pots and pans (check manufacturer's instructions first)

Milk glass

Pewter

Rubber tools

Tin

Wooden spoons

Here are a few more dishwasher "don'ts" to remember:

Don't spill dishwasher detergent on flatware; it can cause dark spots.

Don't use detergents containing chlorine, to avoid the release of chlorine fumes in the kitchen while running the dishwasher.

Don't jam too many pieces into the silverware basket overcrowding can cause items to become scratched.

Don't mix sterling or silver-plate and stainless-steel flatware in the dishwasher, even when using the Rinse-Hold cycle. If the metals come in contact with each other, a reaction between the two metals can damage both finishes. (Since most knives, including sterling ones, have stainless-steel blades, keep them away from other silver pieces, too.)

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