How do you get rid of grey stain off silver?

Detector Wars

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Nov 26, 2008
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Had a good outing, found three sixpence and one threepence, common to find them with a thin film of grey whatevereitis on these small silvers. I don't usually post my finds but this has gone on long enough that I'm looking for extra info.

All four coins I found have this grey stuff:
IMG_1333.jpg

Not pictured is the fourth silver, it was scratched (pinpointer battery went flat, miss-pinpointed the coin) so I'm using that to experiment how I can clean it.

I've tried vinegar before, didn't seem to do anything, trying it again this time I'll leave it in vinegar for a lot longet, see what happens. Any practical tips? Does anyone know what this grey stuff is, do you guys get it in the US?
 

CincinnatiKid

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Oh yea! Another cleaning question.
I'm known for nearly exploding microwaves when cleaning coins, so don't listen to me.
A cleaning/preservation forum exists here.
Also, member frankn, previously posted a step by step hydrogen peroxide cleaning method. Please view.
GL
Peace ✌
 

Carolina Tom

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Rub the coin with water and baking soda, and the tarnish will magically disappear. It is slightly abrasive and alkaline. It will remove the tarnish and make the coin look new.

Coin collectors do not like cleaned coins. They say that it reduces the value. I only clean mine if they are really grimy. I am not interested in the coins value, only that it looks good to me!

Best of luck!
 

against the wind

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Try this on the coin that you scratched,, as has been said,, all you need is to dampen the coin and sprinkle Baking Soda on it. Gently rub it between your fingers and just like magic the Silver Oxide, (grey matter), will disappear. I always check for Key-Dates before using this method. As has been previously stated, cleaning a coin takes away from the resale value of a collectible coin.
What a lot of people don't understand is that a coin that has been buried for a long time, is usually graded with a "Environmentally Damaged Tag" This grade tag will reduce the red Book Value to 10% of what it was originally listed as. EG: AU58 silver 1/2 dollar listed in Yeoman's Red Book for $45K
Graded by PCGS,,, AU58 Environmentally Damaged,,, sells at Heritage coin auction for $4,500.
Very sad but true. Another reason I don't worry about cleaning most of the silver coins that I dig.
 

Charlie P. (NY)

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Silver tarnish is not from oxidation. The composition is sulfur from the air and soil forming Ag2S, so it's actual silver sulfide.

If you have a coin you want to clean, and you don't care that cleaning it may reduce the value, here is one method.

Take some aluiunum foil, boil some water, and then get a supply of baking soda (aka: bicarbonate of soda & sodium hydrogencarbonate) and table salt (sodium chloride). Line a bowl with the foil, add a teaspoon or so of baking soda and a sprinkling of salt, then just add boiling water. The tarnished silver object can then be placed into the water, making sure there is contact between it and the aluminium foil, and the silver sulphide tarnish will quickly disappear.
 

austin

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Silver tarnish is not from oxidation. The composition is sulfur from the air and soil forming Ag2S, so it's actual silver sulfide.

If you have a coin you want to clean, and you don't care that cleaning it may reduce the value, here is one method.

Take some aluiunum foil, boil some water, and then get a supply of baking soda (aka: bicarbonate of soda & sodium hydrogencarbonate) and table salt (sodium chloride). Line a bowl with the foil, add a teaspoon or so of baking soda and a sprinkling of salt, then just add boiling water. The tarnished silver object can then be placed into the water, making sure there is contact between it and the aluminium foil, and the silver sulphide tarnish will quickly disappear.


Best check the texts. Air causes tarnish. Google tarnish...
 

lastleg

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I suggest not applying chemicals including acidic food flaverings to coins. Not to say there aren't
safe alternatives.
 

Mr.T

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!938 6p.jpg Coin was black - way worse than yours-before baking soda- foil- hot water method. I line a pot and keep the water heating a while. Sometimes need a repeat. Wouldn't recommend it on Excalber- but great for normal coins.
 

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RustyGold

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As a jewelry manufacturer for a decade, if you don't care about the coin if tested, I would heat it up with a propane torch and put it in sparex (silver and gold cleaning solution) and see what happens!
 

OP
OP
Detector Wars

Detector Wars

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As a jewelry manufacturer for a decade, if you don't care about the coin if tested, I would heat it up with a propane torch and put it in sparex (silver and gold cleaning solution) and see what happens!

Thanks, I don't have a propane torch, might try heating it up another way. How hot does it have to be?
 

gunsil

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Best check the texts. Air causes tarnish. Google tarnish...

Charlie is correct, it is not the air causing the tarnish, it is the sulfur dioxide in the air that causes the tarnish. Urban areas will often have more sulfur dioxide in the air than some more rural areas. When you are behind a car and smell the "rotten egg" smell from it's exhaust you are smelling the sulfur dioxide, which is also produced from coal burning power plants. If there were no human made pollution of the air there would be little sulfur dioxide in the air and pure air will not tarnish silver.
 

gunsil

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Boy Rusty, that's the hard way to do it!! As a silver and gold jewelry maker for forty years I use Tarn-X to clean tarnish from silver. Tarn-X is available at Lowe's and many other stores, and is easy to use, just dip and rinse, tarnish gone. It is superb on chains and other jewelry where it is hard to clean inside links or designs. Only thing is that if the silver is very tarnished it will have a dull clean surface after dipping and rinsing so a rouge cloth will be needed to restore the shine. This stuff is also the best on sterling flatware.
 

Charlie P. (NY)

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Best check the texts. Air causes tarnish. Google tarnish...

"Air" is 70% nitrogen and a lot of other gasses - including oxygen and hydrogen sulfide. Ask a SCUBA diver about the difference of air vs. oxygen. Silver reacts with the sulfur to cause tarnish. Cigarette smoke, vehicle emissions, home heating, and especially coal-fired utility plants - all dump sulfur into the "air".

You can make silver oxide - but it's so tricky the process has several patents.


 

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