You can quickly restore the blades of your knife that shows signs of carbon residue and staining. Knives that are held over a burning flame may discolor and accumulate a buildup of carbon residue on the blade. Steel knife blades are rust resistant but will still begin to rust and tarnish if they are not maintained properly. Clean the carbon stains from your knife to restore its look and protect its functionality for years to come.
Hold the stained knife firmly on the cutting board so that the blade is pressing down into the board's surface.
Add a couple of drops of metal polish directly onto the stains on the surface on both sides of the knife's blade.
Rub the polish into the carbon stains on either side of the blade in a tight circular motion using a soft all-cotton cloth. Keep the sharp edge of the knife pressed down into the cutting board as you work to reduce the chance of injury.
Wipe the length of the blade with a clean portion of the cotton cloth to remove the polish and from its surface. Examine the success of your stain removal efforts and apply additional polish if more polishing is needed.
Wash the knife's blade in hot soapy water with a nonabrasive scrubber. Dry all parts of the knife completely to prevent rust.
Give all the metal parts of a non-food knife a protective coating of WD-40 to complete the restoration process. The silicone spray will cling to the surface of the metal and repel the moisture that will cause a knife to tarnish.