I have had a Sambar stag handled Puma knife (Hunter's Pal) since 1965 that is still in good shape, though is has darkened some from use and age. With frequent use I think there's enough body oil to keep the stag from drying out, but I don't think a little mineral oil would harm it We sold PUMA knives where I worked in the 60's and 70's and I collected (hence my screen name) them until the prices got ridiculous on the vintage models. The stag they use these days is different (probably elk or deer), but I would think it is probably just as durable. I have bone scaled pocket knives that have shrunk and some that got attacked by little beetles; Delrin will change color sometimes. Canvas/Linen Micarta is probably about the most resolute material for a knife handle.