Care and cleaning. To retain its warm-white color, ivory mustbe exposed to light. If you always keep ivory-handled knives in a chest or a piano’s ivory keys covered, they will eventually darken and yellow.
Dust ivory with a soft, clean cloth. Wash ivory in mild soap and water, rinse, and dry it. Buff it with a clean woolen cloth. Don’t soak pieces such as jewelry or knives; water can soften the glue that holds the ivory in place.
To clean ivory piano keys, pick up a small amount of baking soda with a slightly damp cloth and gently rub one key at a time. Wipe the keys clean with a damp cloth; buff them dry.