Rough green "stuff" on antique salt cellars - how

[muraille]

I have two antique salt cellars from Germany, .800 silver. They were not cared for and have rough areas of green stuff which I cannot remove with silver polish of any kind. Is this from the copper in the silver? Could I use an acid to remove? Or is wheel polish the only way to go? Thanks for your help.
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[JLDoggett]

it sounds like salt-bloom from salt being stored in them. Over time the salt absorbs moisture and leeches the copper from the alloy forming a hard crusty deposit. I would immerse the item in hot water and let it soak a bit (I have even boiled pieces to remove the scale). If not vinagar may disolve it. A wire wheel should be your last resort, though there may be some pitting below the crust.
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[muraille]

I've simmered the pieces for some 6 hours. It helped for the lighter areas. I'll try the vinegar for the harder crust - thank you.
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[dragonflywink]

I've dealt with salts and salt spoons for years, the best advise I've found concerning salt damage (and general care and cleaning) is in this link: http://www.silversmithing.com/care.htm#Advice

I recently cleaned a Viking ship salt and spoon with large areas of heavy black tarnish and crusty green oxidation, after the ammonia treatment (three 10 minute soaks, gently rubbing with fingertips between soaks), the silver had a cloudy white film, gentle polishing with a pink polish and then a second polishing with a very gentle polish with tarnish preventative gave me a nice finish without having to resort to machine buffing.

~Cheryl


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[muraille]

Progress report: the 3 ammonia baths worked and removed most of the crust. For a really bad spot that was left on a rounded foot, I used the vinegar (white distilled) and it melted away what was left. So thanks to both of you, I am on my way to having two usable salt cellars. Still have a lot of polishing to do!
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