All my dice are cleanable!
Take a soft microfiber cloth and moisten it slightly and clean the dice, if you must use products don’t use anything harsher than regular soap or dish soap. They can affect the dice and make them cloudy, or accidentally remove ink.
If you own dice with silver chrome ink for the numbers, don’t let the numbers get in contact with IPA or other alcohols, even regular alcohol for drinking. The chrome effect will disappear if you do 🙁