How to keep mummified mouse preserved?

While a shed was being cleaned, a naturally mummified mouse was found in a box. It no longer has fur, just tight dried skin over bones, and through my glove felt not unlike a dry dead leaf. For now it's in a baggie with some silica gel packets, but I'd appreciate tips to keep it nicely preserved and able to be displayed. I'm a bit worried about some white specks potentially being mould starting due to lots of rain lately, too. I'm not too fussed about the aesthetics of that, just the possibility of it messing it up. I'm new to preserving things, so please eli5 :)