Handles, knobs and fixtures made from bone inevitably yellow over time. Although natural aging adds character that appeals to some, restoring bone to its original creamy color is a simple process if you know what to use. Harsh cleaning agents typically don't work well on organic materials, which tend to be more fragile than synthetic materials. However, several common household items are safe to use on bone without causing any damage.
Pour approximately equal parts of hydrogen peroxide and water into a bowl. Adjust the amount of each liquid according to how many handles you need to clean.
Dip the corner of a soft cloth into the solution and use it to wipe down the bone. Rub with significant pressure, and be careful not to miss any spots.
Use the dry end of the cloth to buff the bone dry.
Repeat Steps 2 and 3 several times, alternating between wiping on the solution and buffing it out until you see the color changing back to a creamy white. Soak a soft cloth in the hydrogen peroxide water mixture and wrap it around the bone handle as an alternative method. Allow it to sit for a few hours.
Use a mild dish detergent and water to remove any traces of lingering peroxide.
Moisturize the bone by rubbing it down with mineral oil. Allow it to sit for about 12 hours and then buff with a soft cloth.