Cents and Corrosion

I seem to somehow always have more cents than any other US coin..lol, So I taught I might start up the small cent type set once again.

I know that they can corrode though..and that bothers me.

How worried should I be about it, is it a problem, or does it not happen often?


stainless

 

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The nice, natural brown toning on copper is a very good barrier against corrosion. If you buy problem free examples you should have nothing to worry about. Unless you live close to the sea, as I believe the salt air can damage them further (hopefully someone else can verify/dismiss this claim).

If you are going for red examples, these must be treated with much greater care if you want them to stay red. I would recommend intercept shield 2x2s, desiccants, and perhaps some shinny strips of copper stored along with them as well.

 

You want to be pretty concerned about it IMHO, if you want to have a nice collection of cents. Corrosion is one of the hardest things (atleast IMHO) to fight with copper coins.

Keep them in a nice dry enviroment, and check them every so often to make sure no corrosion is developing on them (as you don't know if they may have come in contact with corrosion in the past.) And if you ever need help removing corrosion, drop me a pm, and I can help you out hopefully. Best of luck, and happy collecting. :thumb:

Phoenix

 

k, thanks for the help guys...and will do Kool Whip


stainless

 

To start with the so called natural brown toning on Copper is NOT a barrier against corrosion. Secondly if you have salt in the air I'd be carefull breathing it. The smell near an Ocean is not salt. It's to heavy to float in the air.
Not meaning to bore you but when bare Copper, Brass or Bronze is exposed to air, which contains Oxygen, it reacts to form Cu2O, Cuprus Oxide. Slightly redish brown. As the Cu2O is further exposed to Moisture, water or H OH, and Carbon Dioxide, CO2, in the air, a further reaction occurs forming Copper Carbonate [CuCO3-Cu(OH)2]. This starts as brownish green, continuing towards green. Now if you live in an area where coal has been burned or a steel mill, you may have SO or SO2 in the air. This too will react with Copper and form a Sulfite or Sulfate on the coins.
Corrosion, toning, staining, tarnishing are all terminologies of the effects of one substance on another. Coins do all of these. The main thing is to keep any coins away from other substances. Especially any gasses.
This means don't breath on them either.

 

Oh! One more thing. Most salts are Sodium Chloride. This is known as a electrovalent compound meaning the atoms of each are held together loosely and in the presence of a liquid, water, the atoms of Sodium and Chlorine float around individually. They do not go out of the water but occationally some of the Chlorine may escape into the air and that is what you may be smelling in the area of an Ocean.
Of course someone may have just sprinkled some salt on a hamburger near you.

 

Use Intercept Shield products , they were developed by Lucent Bell Labs and were 1st called Corrosion Intercept Bags , they will neatralize sulfide gasses which cause most corrosion .
rzage

 

Carl, I don't know what part of the US you hail from but here on Long Island when you get near the ocean you get a whiff of clean fresh sea air and it doesn't smell like chlorine....the backyard pool smells like chlorine (LOL).

 

First, let me apologize for providing the poor information that cuprous oxide provides a protective barrier. I see that Cu2O can naturally change to cupric oxide (black), copper carbonate (green) and other things too.

However, I am curious about its propensity to change in the absence of a catalyst. Having stored my childhood collection of wheats in a Whitman folder for 25 years with no ill effect, I would guess coin encapselation in any of the readily availible inert plastic holders would be more than sufficiant protection for generations. Although if one lives in a harsh enviroment for coins (heavy pollution or moisture) additional protection is needed. Again, this is a personal guess, hopefully someone with broader experience can accurately decribe the real-world danger faced by brown copper coins to unwanted corrosion.

Secondly, while ocean air does not contain some terrible mix of free floating sodium and clorine ions, it does contain salt (NaCL). Wave and wind action aerosolize sea water and loft it into the atmosphere. Nothing special happens to change the composition; These tiny droplets contain all the organic and inorganic compounds you would expect to find in the ocean. I dont know if the salt air is expressly bad for coins, but its something I'd rather not find out the hard way.

 

Thankyou, I was beginning to think what I was smelling around here was chlorine.

 

That is true of the airation of NaCl in the air due to tubidity in the water from harsh air movements. However, that only last a short time due to the wieght of the Sodium. Partially mixes with the moisture in the air but settles out fast.
As to coins changing without a catalyst, metals do not need a catalyst when Oxydizing or reacting with other gasses in the air. However, that all depends on if you consider temperature a catalyst. For example SO or SO2 in the air readily mixes with H OH otherwise none as H2O, moisture or water. Chimically water is Hydrogen Hydroxide and that is why it so readily mixes with SO or SO2 to form a Sulfite or Sulfate Acidic substance H2SO4 is the worst of the substances to react with Copper. The Cupper in coins replaces the less molecular reactive Hydogen. In some areas this is so bad it is commonly known as Acid Rain and destroys almost everything. Numerous individuals in such areas constantly complain about their Copper pipes in thier house turning green.
Back to your coins in a Whitman Folder for 25 years. It is obvious that where they were stored there was little access to moisture and Oxygen. Expecially moisture. You mentioned FOLDER, not album. If you take one of those coins out of that folder you would see a shinny substance on the rear of the slot for the coin. This is glue from the manufacturing process. If moisture would have been sufficient in that area the glue would have probably stuck to the coins. This is why you see many coins with glues, lines, discolorations on the reverse side.
As to what is called Salt, NaCl, yes it would attack many coins. Remember that NaCl is an electrovalent compound and in the presence of moisture, the Chlorine would attack the Copper.
As you stated almost any of the present coin Albums, plastic rolls, 2x2's, etc that seal the coins from air, moisture, etc. are just as good as any.
There is constantly on these coin forums debates as to which is the best. My idea is that that is like asking which car is the best, which milk taste better, which lady shoud I marry, what stock should I invest in or who has the worst mother in law? All are to contraversial.