I know I’m not supposed to wash it because that will take off the bloom.I’ve heard of using sandpaper but I know that can also remove the Bloom along with maybe even some of the eggshell itself. I’ve tried to wipe it off with a cloth but it doesn’t budge it’s hard cake. The bit I am able to pick off easily actually removes some color and bloom. I don’t want it contaminating my eggs. I just don’t know what the best thing is. I prefer to keep them on the counter for a few days before I decide to put them in the refrigerator for longer-term. If I am giving them away or selling them I wash them and put mineral oil on them so I’m not talking about the ones I am Going to sell or give away. These are the ones that will stay within the family so they are used to them not being washed until they are ready to use them. If it’s not poop then it’s pine shavings sticking because Marans eggs are always like glue.