I had some responses to my recent post regarding this problem and so
gathered some more detail from my daughter.
The story - My daughter, an objects conservator, had sent a large
exhibit of priceless early American silver to a museum in Japan
where the display cases which were provided for the objects were
made by the museum there and did not follow the required specs and
guidelines. The result was that the entire collection was turned
black in less than three months - Great consternation and beaucoup
de work to get it restored.
My memory of her description was close, but not bang on the money.
Following my comments is my daughter's recollection of the situation
which, as you will see, mentions a number of possible causes as well
as the paint. When I last had spoken with her about this event, she
and her staff were right in the middle of the unfolding catastrophe
and thought the problem was the paint on, or in, the cases. At that
point they perhaps had not seen all the other screw-ups that may
have been, individually or in combination, the cause of the
Also, following, you will see the guidelines for silver display used
at the Boston Museum of Fine Arts for silver display. These may not
be practically applicable to retail jewelry shops where objects must
be more readily accessible than in museums where security is a
higher concern and where there is very little need to handle the
objects on exhibit.
With regard to the "PVC paint" she mentions in her description -
there are several possibillities and I'm not clear which applies.
First - there is vinyl paint, paint containg PVC's as we know them,
Second - there is paint designed to paint onto PVC plastics - This
paint contains lots of very volatile solvents and outgasses like
crazy, a likely candidate.
Third _ "PVC" is abbreviation for "Pigment Volume Concentration" in
the paint industry and depending on that value in a given paint, may
require addition of extra binders etc which in themselves might
In any case, the museum display case guidleines below will give you
a good idea of what to watch for - Basically stay away from paints
and all smelly organics if you can.
I hope this is helpful or satisfies your curiousity.
Marty Hykin, Victoria BC.