Is there a way to strengthen or keep intact the (undead) skeleton monster bones elements or compositions/components without using guts digestions?

Question

I want to know if there is a scientific way for skeleton monster to keep their hardness intact or strengthening it without getting wear or weakened from the elements. since they have no guts or internal and external organs in general except bone, so they cant digest or eat to gain materials or minerals needed. spilling milk over their bone actually wont work from what i found out recently, infact the milk can make it worse (but correct me if i am wrong), and i am not sure trying to bath themselves with sunlight can give them vitamin D with only their bone left intact, beside i see some bone left outside getting so dried up and create a crack on their bone. if its actually a possible method, how long does the skeleton need to bath on sunlight or the temperature that is safe or dangerous for them to take sunlight bath?

• and i dont mean dipping them or lacquering themselves with metals, even with that, i believe it still will give crack or shatter the original bones inside, due to the internal force if getting hit or due to the heat difference. or putting armor in general including softer/non-rigid armors, if its not clear enough.

• also answer like they should stay inside forever to keep their bone structure from wearing due to the elements or something similar, is out of the questions because thats not my main question or my concern.

• also changing the bone to be made of metal or something else is out of the questions, this is mainly regarding the usual bone composition or component like calcium or magnesium. and i want to know in a natural way rather than artificial made up high tech tools such as nanomachine, i know its too late since someone quickly answer using that but so be it.

i hope this is at least understandable enough....., and feel free to correct my grammar and tag to be appropriate, because i dont even know what tag is appropriate for this.

from:https://en.wikipedia.org/wiki/Skeleton_(undead)

ps: i am not sure are mythical-creatures tag is correct for this....after all....Skeleton is real.....they are living inside YOU!

Answer 1

The only scienc-y way is to have some sort of nanomachines covering the bones and have those repairing the bones as soon as some wear and tear appears.

However the nanomachines would need to be supplied somehow with the needed elements. I guess a way would be to soak the skeleton in sand, where the nanomachines could harvest silicon, calcium and other elements. A silicon based skeleton would be more similar to rock than conventional bones, thus why not?

Answer 2

Undead liche warriors are of course a staple of the marauding hoardes of the madder sort of Witch King. Sadly, without some pretty powerful dwimmery or high technology, there's just no merely natural way of doing what you want.

Essentially:

1. Living bones regenerate by taking in nutrients from the blood; they are able to direct their own growth and regeneration via genetically driven mechanisms (e.g., osteogenesis).
2. Dead bones lack resources & metabolism and therefore can not engage in any living processes.
3. Magic, of course, can, at great cost, mimic these living processes. Science can do the same. But those aren't what you want.

Without any pretty deep magic or technology, dead bones will remain dead and simply can not, using purely natural means, like sloshing them with milk or exposing them to sunlight, be animated or restored in the way you want. You are asking for living bone to exist within a lifeless composition, and that's not possible given your constraints.