Red Roger:
The first thing to do is closely examine the overall plating of the tray.
Are there any wear spots down to the copper layer? ( usually due to early cleaners eroding the plating)
If so and it is desired then a re-plating maybe desired if the wear marks are distracting.
Just remember re-plating does cost a pretty penny.
Some of my antiquing dealer friends do re-plating but they wait for "market prices" to be low as while the actual silver is minimal there is the "silver market costs" a silversmith may charge.
Are the pastes just in the "corners, deep edges, deep grooves"
If so then a silversmith may have one of the new generation cleaners that will allow for the lifting and removal of old paste cleaners. These usually do the cleaning without altering the patina which gives the tray "life".
Some times a baby's first toothbrush (ultra soft bristles) is all that is needed to clean old dried paste. Also a wooden toothpick to get really deep spots dislodged works.
Hope this helped a little.
Respectfully
Keith W Brown
