Hi Mike. Welcome to Orchid! I’m not a true expert on tarnish, but
most of my pieces are silver with antiquing too, and I do have some
browning of the silver over time. I was wondering though, have you
considered using the good old “liver of sulfur” for antiquing? It’s
tried and true, and very easy to use. (I am sure you are familiar
with it) Also, Silver black (hydrochloric acid) works well if you are
painting the black on. The whole idea of lacquering a piece of
jewelry just feels wrong. lacquer is for wood, and even then, I
prefer oil finishes.
But, perhaps in this situation the best thing to do would be to side
step that issue and ask instead, “Who Moved my Cheese?” and start
"Thinking Outside of the (plush, velvet, hot-stamped) Box" to come up
with a different solution for the packaging itself. First of all,
make it very clear to your customer that you want to continue doing
business with them and you are doing everything possible to solve the
problem, and assure them that it WILL get worked out!
Then...why not completely remove the option of their displaying your
products in the clear baggies by using either “Anti-Tarnish flannel
pouches” (like the ones for old silver flatware - Rio Grande Display
catalog item number 455-340, page 65) or use small cardboard boxes
with an anti-tarnish tab (page 202) inserted in each one. That way
the piece could breathe.
Now, I understand that the cost may be prohibitive for the pouches
and boxes, maybe wrapping each piece creatively in a nice
anti-tarnish tissue paper (page 75) or swatch of anti tarnish fabric?
Or possibly using glassine envelopes similar to photographic negative
carriers? Or, maybe small manila envelopes, or small paper bags
stapled/taped shut (page 74). Then they have to “let the piece out
of the bag”.
Just some ideas. I wish you luck!