As they are eggs preserved.
Protected like fragile eggs.
as if they were hidden pearls
As if they were eggs, carefully protected
As though they are (F) protected/covered whites/eggs
As delicate as an egg under its shell
As if they were eggs, safely hidden
As though they were sheltered eggs
(Fair, charming complexion, they will look) as if they were eggs protected from dust
Just as though they were eggs carefully guarded (- of pure and unsoiled character)
(Delicate and pure) as if they were (hidden) eggs (well) preserved