Baking soda and vinegar, Watch out!

[mastereagle22]

Well the other day, after reading someone's post about using baking soda and vinegar and water to clean coins, I decided to try it. Grabbed a handful of dimes and quarters and tossed them in a plastic container, put in a very small amount of baking soda and some plain white vinegar. After 5 mins the coins were really shiny but the dimes and one of the quarters looked like someone had drug them on concrete! Scratched and pitted everywhere. I don't what I did wrong but I know I will think twice before I do that again, and I will NEVER do it with a good coin!

[camb1]

Do you have a rock tumbler? If so use 1/2 cup ammonia, 1/2 cup water, handful of white aquarium gravel and 1 tsp of dishwashing liquid. Run tumbler for 2 hours and check. I have ran up to 5 hours before.

Do not put pennies with clad silver.

Do not use on old silver coins.

[mastereagle22]

No I haven't managed to buy one yet.

A quick way to knock off all the crud from the clad is to throw it into a plastic container, I use a gatorade bottle, toss in some sand and soap and shake for 10mins. It works pretty good and is cheap. I am saving up my pennies for a rock tumbler.

[chong2]

no, bakingsoda vinegar and salt..... watch out

[Eu_citzen]

Bump! I think I'll reply as I have used this method with fair success. Did not see this topic before.

I don't know what composition your coins are/where. It WILL kill your pennies though. (tried it on a 1992 D one cent I found once if there are bubbles rising form the coin remove it directly!!)

Use approx 4-6 table spoons water and 1 table spoon vinegar and a little salt. You want a low concentration of acid. (a bit of Chemistry knowledge does help)

I have used this for: (composition and example from Swedish coins, alloy is stated)
Nickel (25, 10 Öre after approx 1962)

Copper & Nickel alloy (Modern 1 & 5 Kronor)

40% Silver (25 Öre, 10 Öre and more before 1962 or so)

Copper (5 Öre, 2 Öre and more)

89% Copper, 5% Aluminum, 5% Zinc and 1% Tin (Swedish 10 Krona, modern)

I prefer to look often, 5 minutes is often good enough.

When done with acid treatment put it in a bowl filled with water and add baking soda/powder to this to neutralize the acid, you can do this on both sides of the coin, just turn it around.
No need to add more baking soda/powder more then once the water will also help to neutralize the acid.

Wipe it dry with a piece of paper or something similar.

Only put in coins with same composition.

Hope it helps!

Good Hunting!
Eu

[mastereagle22]

It really pitted my nickels

[Eu_citzen]

Hehe I bet!! Plain Vinegar is a bit to strong that is why I have water in it.

Good Hunting!
Eu

[riverite]

Yep add salt to vinegar turns to hydrochloric acid

[BuckleBoy]

Yep add salt to vinegar turns to  hydrochloric acid

I'm blowing the BS horn on that one.   


Salt just dissolves.  Vinegar (acetic acid) is what does the work. 



-Buckles

[Shortstack]

There's a tip that I saw on the DIY Channel for cleaning tarnish from silverware that might work for cleaning tarnish/crud from silver coins. Take a shallow container, lay a sheet of aluminum foil (shiny side up) over the bottom; place the silverware (coins? ) on the foil. Then, put a teaspoon of baking soda into the dish and pour boiling water into the container and let stand. Supposedly, the hot water with soda causes the tarnish to fall to the foil. I have not tried this, but it is on a do-it-yourself channel and has probably been verified. It surely should not cause any etching on the coins.

[jerry s]

Shorty,

I'll try to keep this in layman's terms. It will surely work, what they have done is use the simple reactivites of metals in solutions, (Galvanic Series) so that the less noble metal (in this case Aluminum) will give up electrons to the silver and "reduce" any corrosion products and thus clean the silver coin.

Someone else mentioned about not putting disimilar metals in the same cleaning bath at the same time. This is also a result of the Galvanic Series, the less noble coins will give up electrons/form cations and corrode away preferentailly to the more noble metals such as silver, gold or platinum. This is exactly the process that makes "Galvanizined steel" survive soo much longer than raw steel, the zinc is less noble than the steel and acts as a "Sacrificial Anode".

As far as acetaic acid and salt forming HCl. Thats Alchemy.

As fars as using SS for an anode for cleaning in NaOH solutions. This is probably the best "household materials" method to use, but make sure it is 304/316 as they are refered to as Austentitic SS and the most corrosion resistant due to there high Nickel and Chrome content
(a simple check-these are non-magnetic, 304 can be magnetic depending upon wheter it is anealed or cold worked ). Platinum makes the best material for anodes , but very $$$$$. Electrical grade graphite is also very good in that it does not enter into the reaction and would not require replacement each time you use it to clean coins. You can probably buy some at mcmaster-carr.

Final word of caution, if one is cleaning Al artifacts, do NOT put in NaOH solutions. They WILL completely disolve.

I have gained alot of interest in the cleaning processes and will set up a Graphite-NaOH bath. I'll keep you informed of the progress/results.

On Edit.
This is the McMaster P/N that will probably work well as an anode, 1763T23. Its $11.00 plus shipping so it won't break the bank like a platinum wire will. Its 1/4" by 1" electrically conductive graphite. I just ordered some and will keep you all posted.

[greydigger]

If anyone wants some graphite PM me, have a bunch.

How does the vinegar (and salt?) differ from hydrogen peroxide?
Hp is very cheap here where vinegar is more than twice the price.

Or are we talking different things.

I tried TarnX on a penny that I couldn't read and it mostly ate it up.
Maybe that was because the corrosion was so deep, but it also turned it orange.

Not good.

Grey

[Eu_citzen]

Grey Vinegar will eat your modern pennies...Just a note for you...

[greydigger]

"Vinegar will eat your pennies"

OK and hydrogen peroxide will not?

or it will also

Grey

[Eu_citzen]

"Vinegar will eat your pennies"

OK and hydrogen peroxide will not?

or it will also

Grey

Never tried peroxide. And don't get to many pennies to try on either.
But vinegar is the death for a modern pennies at least.

[Michigan Badger]

For cleaning dug silver the only safe way I've found is the baking soda--hot water--aluminum foil method. This is how I cleaned most of my ocean recovered pieces of 8 (mostly from Florida waters). The salt water encrustation fizzes away fast.

For dug clad and common coins headed for the bank I use a rock tumbler with aquarium gravel/water, and a tiny bit of Dawn dish soap.

All non gold buried items corrude over time and this always means lost metal (pits, etc.). The soil they're buried in is what determines the extent of damage.

Badger

[cosmic]

I read to use washing soda with the aluminum foil..