Silver Cleaning

February 21, 2004 6:47 AM

I need to know what kind of metal, in combination with Bicarbonate of Soda (Soda Ash) , will clean silver.

I was at the Seattle Home Show last night and a woman was selling a "Silver Cleaning Kit" for over $25. The kit contained a thin rectangle of metal along with a bag of white power. The powder (she freely admitted) was Bicarbonate of Soda, commonly available in any grocery store.

To clean silver, she prepared a solution of warm water and the powder, put the metal plate in the bottom, and put the tarnished silver in the water. In seconds the tarnish was removed.

The woman said that the plate contained 11 alloys including brass, copper, tin and so forth, and that the chemical process was "reverse electrolysis."

We almost coughed up the $25. but then I realized that the metal had to be something simple, and that I could probably find out what it was with a Google search or two.

However, all of my efforts to figure this out have been unsuccessful. All of the hits for "reverse electrolysis" involve electrical current.

Does anyone know what kind of metal this is?
posted by jeffbarr to Home & Garden (8 answers total)

I don't know what the metal could be, but washing silver jewllery with toothpaste is effective.
posted by riffola at 6:57 AM on February 21, 2004

Aluminum. I heard this trick when I worked in an airplane-parts plant. Unfortuately, it may be a certain *type* of aluminum alloy (thus the saleslady's "eleven herbs and spices" bit), but I can't recall. You should be able to get a thin plate of aluminum from the hardware store.
posted by notsnot at 7:27 AM on February 21, 2004

You can use aluminum foil I think. I saw that Mr. Wizard damn it!

http://www.creativekidsathome.com/activities/science_experiment1.shtml
posted by jopreacher at 7:43 AM on February 21, 2004

I have one sitting infront of me. It's called Qwicksilver®. It says on the back that it's activated by sodium carbonate, or soda crystals (that you use to clean drains etc.) not bicarbonate of soda (that you use for baking(?))

It says it's a "self-acting electrolytic cleaning plate" but it does look just like a plate of aluminium with a few holes in it.

While I was looking into this, I did read on the packet of soda crystals that it says they should not come into contact with aluminium. Coincidence?

The Qwicksilver® plate cost around £6.95, about 15 years ago.
posted by Blue Stone at 8:03 AM on February 21, 2004

A search for "electrolytic cleaning plate" threw up this amongst lots of info:

I love this question!

The usual tarnish on silver is the black sulfide. The cool thing about this is that you can instantly remove the tarnish from any silver item with commonly available household items, and I do mean fast!

Aluminum is far above silver in the activity series for metals, and in a suitable solution will reduce the silver in the silver sulfide, reforming silver metal. The reaction is spontaneous and rapid in warm water:

2Al(s) + 3Ag2S(s) + 6H2O -> 6Ag(s) + 2Al2(OH)3(s) + 3H2S(aq)

So, all you have to do is get a container big enough for the silver item, partially fill it with warm water and a couple tablespoons of sodium bicarbonate, a.k.a. baking soda, place some clean aluminum foil in the container and then just dunk the tarnished item in the bucket. The silver item has to touch the aluminum. It works in a few seconds, no scratches, no muss, no fuss, and then all you you do is rinse the item off. There is no adverse environmental impact, none of the ingredients are in any way toxic (they are food grade!), there is no abrasion or scratching of the silver and you can use your bare hands to remove the treated items from the solution. Just rinse and dry the silver when you are done, & pour the "used" solution down the drain! Re-use or recycle the aluminum foil.

A big old aluminum cooking pot works well as long as you use some steel wool on it first to remove the native aluminum oxide. This "treatment" works on silver plate, jewelry, any tarnished silver. Try it friends! Better living through chemistry!

From here.

Also later in the thread:

"The trick is to use "washing soda", not baking soda. Arm & Hammer makes the product. Some grocery stores sell it; sometimes K-mart or that type store will have it. It works well with the aluminum plate I bought at a boat show a few years ago. Adding foil to the bottom of the glass container, then the plate, then the soda, then boiling hot water works!"

posted by Blue Stone at 8:11 AM on February 21, 2004 [1 favorite]

I do this all the time at home using aluminum foil. It isn't as efficient as the more pricey products, but it doesn't cost as much either. Here are my instructions:
Take a square of aluminum foil (as long as the roll is wide) and put it in the bottom of your sink (unless your sink is white, which might stain). Put about 1/4cup of table salt, and about three tablespoons of baking soda on the foil, and fill to a decent depth with VERY hot water (boiling water works fastest) and dunk your silver item into the water, being sure to touch the foil.
You'll have to change the foil every once in a while, and you can get through a whole silver service in nearly no time!
One other thing to be aware of, it does raise an awful sulphur odour, so don't have company over the same day!
posted by nprigoda at 2:32 PM on February 21, 2004 [2 favorites]

Response by poster: Thank you everyone, you just saved me a lot of money.
posted by jeffbarr at 4:25 PM on February 21, 2004

Also try lemon juice - or any other citric acid - and the scratchy side of a sponge.
posted by interrobang at 8:47 PM on February 21, 2004