Connected to this but isn't part of the same question.
So, it seems my cat is going into surgery in the foreseeable future, but there's literally no one in the country who would do a chemical analysis of the removed stones, so my options are to either not do it at all, send the stones to a Russian vet lab through 9 circles of sanctions hell, or keep the stones and hope I can analyse them when I move to EU, which I have no idea when that'll happen, but even in the ideal world best case scenario it won't be less than 5 months. Would the stones keep that long?