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Baking soda ingrained into silver flatware after treatment

Q. I tried the silver cleaning trick with antique silver flatware and RUINED it! Now the silver is thickly coated with a white residue and I can't get it off! I didn't use any salt, just baking soda and boiling water; some of the knife blades actually melted! How do I correct and get my silver gleaming again!

Lisette S [last name deleted for privacy by Editor]
homeowner - Metairie, Louisiana
2004

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It's not going to be good news to hear, but that white residue is certainly not baking soda -- which is very soluble and unlikely to precipitate into a thick coat of residue, and would certainly never become 'ingrained' in silver.

It sounds more likely that the residue is metallic corrosion products -- which begs the question of what this flatware is really made of, since silver simply does not corrode like that. The only materials that I know which "bloom" into corrosion pits that look a lot like a "water hardness" deposit are aluminum and zinc, and that would take a while not a few minutes.

The "melting" of knife blades at less than 212 deg. F (boiling water) is a mystery because that doesn't sound like the behavior of any metal that I know of :-(
I would absolutely not use flatware that melts at 212 degrees! Who can even guess what it's made of?

Please tell us something about the history or origin of this 'antique silver flatware' because it certainly doesn't seem to actually be made of silver. How long have you had it? It would seem unlikely to be able to survive washing if it was this delicate unless (possibly) the contact with aluminum foil caused anodic corrosion of whatever strange material it is made of (magnesium?). Thanks!

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey