Protecting hand painted mother of pearl

Jewelry Discussion
1

i am sorry if I am not sending this message correctly, this is a
first for me. We are currently hand painting mother of pearl
pendants which we buy the size of a fifty cent piece. Once it is
painted then we cover it with Envirotec 2 Part resin. At the
beginning of this project we thought that the resin would last for a
long time. But after a few months it starts to peel and it sometimes
yellows. Could you please suggest another method to protect the
painting on these shells. Appreciate any help

Thank You
Edmundo

2 
We are currently hand painting mother of pearl we cover it with
Envirotec 2 Part resin. after a few months it starts to peel and it
sometimes yellows.

i have never used shell, but it’s inner lusterous surface, is very
hard, if rubbed with scotchbrite then it might take finish, maybe
waterbase lacquer would work, i use KTM-9, or spirit lacquer, dp