I always wanted to explain the resin (common) and wood sealer reference when skeletons do patch work. I wanted to art it in a comic form for reference, but I’m a lazy beast.
Resin, you can get more often at craft stores, or wood sealer/glue -same - or any epoxy for sealing is okay to use for animated bones. I don’t know if you can use this junk for taxidermy/specimen preservation, just to clarify, some may confuse the nature of the use. This is for cosmetic purposes. Most skeletons use resin, epoxy, and wood sealant for cracks and typical wear in bones. Usually in the facial structure - the perpendicular plate, the zygomatic bone, commonly in the maxilla (that sees a lot of wear), the ramus mental foramen, anterior nasal spine, and… anywhere else to make your skull look freshly skinned, and sun bleached. Some skeletons go totally bonkers with their sealant application and coat their skull in two or three layers, everywhere. I don’t understand why, it’s a chore to grind off, if you don’t apply the layers evenly you get unsightly opaque patches. And sealant is not permanent, it splints and warps and eventually looks worse than what you had to start with, it’s meant to be replaced.
But resin used sparingly will give your skull a nice patch of shine. Looks really catchy and attractive without detracting from your natural porous surface.
Of course, its a temporary fix. Depending on what sort of spirit, skeleton, cryptid, some will find it advantageous to administer epoxy in joints. Despite being under constant wear from movement (and cloth, don’t get me started), joints don’t grind down and don’t become uncomfortable. Not like the skull or facial region. That’s good though, right? It’d be a bitch bathing in epoxy all the time. That stuffs not cheap either.
No, don’t ask why the skull wears out. It has something to do with being the point of visual focus or something. Some mysticism bullcrap, I don’t make the rules.