I just completed some bird's-eye and spalted maple boxes. What I tried
was a bee's wax finish. Mix was made from bee's wax (75%) carnuba
(24%) and petrolatum (1%) to thin it out a bit. Spread it out and
buffed it in with a coarse terry towel. Works best if wood is slightly
warm. I don't think this will yellow, is fairly water-proof, and since
it seals the surface, *should* stop further "rot".