Plating question

 Purple blossoms on my wisteria are heaven to see and smell
right now. Sue Knopp 

Sue, they were glorious here a couple weeks ago.

Now, my question: Isn’t it possible to plate an already
completed piece, with diamonds still in it? I have a friend who
has a wonderful artist-made piece- and the acid on her skin is
causing black marks on her neck. I suggested she look into
having it plated 22kt over the 14kt. This WAS correct, wasn’t
it? Anne