It is hard to answer any kind of question like this without specific information on the condition of the silverplate object. General advice is to not ever use an aggressive polish on historic silver - to never leave polish or chemical residues in place - and to house, store, or exhibit it with the appropriate acid-free and sulphur free materials and environment, to never handle historic metals with bare hands, so as to reduce tarnish and corrosion. I also need to offer a caveat - the lacquering of historic silver has to be done carefully and professionally. I have seen silver objects that have had severe tarnish and corrosion where the lacquer was not applied correctly, or the surface was not cleaned and degreased correctly, and I have even seen fingerprints etched into the metal under the lacquer. The reason is that if the surface is coated and there is just one spot where it is not, there is greatly accelerated corrosion due to the surface area of the exposed vs. non-exposed areas on the metal. The best of lacquers only last 10 - 20 years depending on the local pollutants in the air. Cheers! Dave David Harvey Senior Conservator and Museum Consultant Los Angeles, CA On Fri, Oct 15, 2010 at 2:51 PM, Marc A Williams <[log in to unmask]>wrote: > I would like to reinforce Kathy's warning. Plated objects have a LIMITED > number of polishings that are possible over their lifetimes. Once the > silver is worn away, which usually occurs unevenly, exposing patches of the > base metal, the object is essentially ruined, unless re-plating can be > considered ethically acceptable. So, they are ideal candidates for a > protective coating application after careful polishing. This could last > 50-100 years, depending upon the ambient atmospheric conditions, and could > eliminate the need for a dozen or more polishings. Instructions for coating > metals are available on the web, or a it can be referred to a conservator > for professional application. > > Marc > > American Conservation Consortium, Ltd. > 4 Rockville Road > Broad Brook, CT 06016 > www.conservator.com > 860-386-6058 > > *Collections Preservation Consultation > *Conservation Assessments & Surveys > *Environmental Monitoring & Low-Tech Control > *Moisture Management Solutions > *Collections in Historic Structures > *Collections Care Grant Preparation > *Conservation Treatment of: > Furniture > Painted Wood > Horse-Drawn Vehicles > Architectural Interiors > Decorative Objects & Folk Art > > Marc A. Williams, President > MS in Art Conservation, Winterthur Museum Program > Former Chief Wooden Object Conservator, Smithsonian Institution > Fellow, American Institute for Conservation (AIC) > > > ----- Original Message ----- > From: Kathy Haas > To: [log in to unmask] > Sent: Friday, October 15, 2010 4:08 PM > Subject: Re: [MUSEUM-L] Cleaning Silver > > > We’ve had good luck with the calcium carbonate method described in the > conserve-o-gram. However I’d like to add an additional note of caution, > since you mention this is a silver-plated trophy, not solid. The amount of > silver on plated wares varies tremendously based on how much was initially > applied and how much has worn/been polished away over the years. The last > thing you want is to polish away the silver layer and expose the base metal > below. So take a good look before you start to see if the silver is already > worn away in any areas and in general go very lightly with the carbonate. > > > > Kathy Haas > > > > Katherine Haas > > Assistant Curator > > Rosenbach Museum & Library > > 2008 Delancey Pl. > > Philadelphia, PA 19103 > > ========================================================= > Important Subscriber Information: > > The Museum-L FAQ file is located at > http://www.finalchapter.com/museum-l-faq/ . You may obtain detailed > information about the listserv commands by sending a one line e-mail message > to [log in to unmask] . The body of the message should read > "help" (without the quotes). > > If you decide to leave Museum-L, please send a one line e-mail message to > [log in to unmask] . The body of the message should read > "Signoff Museum-L" (without the quotes). > ========================================================= Important Subscriber Information: The Museum-L FAQ file is located at http://www.finalchapter.com/museum-l-faq/ . You may obtain detailed information about the listserv commands by sending a one line e-mail message to [log in to unmask] . The body of the message should read "help" (without the quotes). If you decide to leave Museum-L, please send a one line e-mail message to [log in to unmask] . The body of the message should read "Signoff Museum-L" (without the quotes).