Cleaning mother of pearl grips

[cmj8591]

I came by a 1903, Colt Pocket Hammerless that is 113 years old. It is covered with shellac inside and most of the outside. It is complete and seems to have been fire very little. It has factory MOP grips that are also a little stained from the ancient oil. My question is, what is the best way to clean these grips? I don't have much experience with MOP and have never owed a gun with MOP grips and I don't want to do something I can't correct.

 

[ruger 22]

I got this advice from a friend who is a jeweler. A damp soft cloth is your best bet. Do not soak in water or use soap. Just a damp cloth to wipe them with. Stains of age add character.