I have source material here which gives a number of ways
to prevent 925 from tarnishing including;
1.Suitable wrapping paper
2.Special protective paper for silver
3.Storage in transparent bags
4.Invisible surface films according to the Thomas Price process or
the dipping process devised by Dr. Finkh.
Can anyone help with more about number 4?
Unfortunately the source is photocopy with no reference so I can't
find notes or anything else about this.
Any help would be much appreciated,