| Hi Larry,
Mother of pearl reacts to the same environmental influences the same way as pearls do. Since Queen Elizabeth I's ring with a mother of pearl shank still looks pretty good as do some early Byzantine mother of pearl inlays I've seen, I'd say it is just as durable and degrades just as pearls depending on environmental factors and use. That, of course, also applies in the negative sense with bleached and dyed mother of pearl degrading faster than untreated material.
Zeide |