On Wed, 22 Oct 2008 14:28:15 -0700, in rec.crafts.jewelry gruhn
wrote:

From many jewelry supply companies, such as Rio Grande and others, you can buy a
3M product, a black paper that is treated with tarnish retardants. *Small pieces
of the stuff placed with the jewelry in those zip lock bags will prevent the
formation of that tarnish. *

Just curious: Is there any knowledge of using oxygen displacement for
long term storage? vacuum, dry ice, nitrogen...

Not that I know of, at least not in commercial practice. Atmospheric /
environmental controls of various sorts might be more common in places like
museum collections or something, especially with fragile or vulnerable
antiques...

But for normal silver jewelry, such as the OP asked about, oxygen isn't really
the problem. Tarnish on silver alloys isn't oxides. It's sulphides. Keeping
out oxygen isn't really needed.

Peter