Is there any hope for this 2 cent piece

[PhotoRob06]

Originally Posted by hssea

I would leave it alone--it does have a lot of character . When we first started my husband found a 1903 large Canadian cent. I was able to wash it off to get all the detail but then decided it would look "better" if I used copper cleaner--Wrong--now you can hardly see the detail and the smooth dark patina of course it gone and we are left with a very rough coin. I'm hoping that it will oxidize again and that wonderful patina will come back

Simon's right though - 2-cents are bronze & the corrosion will progress until it eats the coin entirely.

I just looked up the content of these coins (90% copper 10% tin = bronze) There are ways to stop the process, but it needs to be treated.

[vvvlive]

I wonder if the sidewalk concrete had an addmix such as calcium in it. Calcium is highly corrosive. If it did contain calcium rain/water could have leached it out over the years and gotten to the coin. Calcium will eat up untreated rebar.

[gameoftag]

Originally Posted by PhotoRob06

Simon's right though - 2-cents are bronze & the corrosion will progress until it eats the coin entirely.

I just looked up the content of these coins (90% copper 10% tin = bronze) There are ways to stop the process, but it needs to be treated.

Any idea on how to treat it?

[PhotoRob06]

Originally Posted by gameoftag

Any idea on how to treat it?

It takes a bit of effort... (Never done it myself).

The following info. came from here: http://www.collector-antiquities.com/89/

Treatments for bronze disease

Treating bronze disease can be a long process. There is no quick solution to its removal.
Heat will temporarily neautralize bronze disease simply by removing the water which is needed for the reaction. Simply bake the piece in the oven at 250 degrees for 30 minutes to an hour.
This is not a cure since as soon as the thing cools down, the moisture in the air may start the reaction again. At best, heating will temporarily stop or slow the advance of the disease. Note: Heat may change the patina color.

Mild Cases

The distilled water method


Using a magnifying glass and a sharp needle to remove any obvious green spots still visible
Soak in distilled water. This may seem to be counter-intuitive since moisture is needed to start the reaction in the first place, but it does work.
Do not use tap water. The chemicals in tap water could actually increase the bronze disease.
Over a period of time, distilled water will attract the chloride ions. As the water becomes saturated with chloride ions, the effectiveness will be reduced.
Change the water periodically. Every two or three days at least.
Keep on for two weeks.

In addition to thorough drying, many reccommend placing the piece in an oven at 250 degrees for an hour.






Serious Cases:

Sodium Sesquicarbonate solution.

Using a magnifying glass and a sharp needle to remove any obvious green spots still visible
Place the piece in a glass container and fill with a 5% solution of sodium sesquicarbonate.
Let it soak for about fourteen days, replace the solution, and soak for another fourteen days.
Then, place the picece in distilled water for about a week.
.

Some people say it helps to heat the mix to boiling to start with for a few minutes.

Some people reccommend a light scrubbing each day or so to help remove surface contamination.

Making up sodium sesquicorbonate
You can make it with equal molar amounts of sodium carbonate (Na2CO3 -also called soda ash) and sodium bicarbonate (NaHCO3 - baking soda ).
For example, a 5% solution would then be 10.6g of carbonate and 8.4g of bicarbonate per 100ml of water.
Use de-mineralized or de-chlorinated water for better results

or

You may go by weight or simple dry measurement, i.e. tablespoons full.
Store the mix in an air-tight container..
Prepare a bath of 8 parts sodium carbonate to 5 parts sodium bi-carbonate.
A 5% solution will remove any patina!!

If there is an exceptionally aesthetic patina to be preserved, try a 1% or 2% solution.
Be warned, though, that it will take three times as long, and has a risk of being ineffective.
After the last soak and scrub, dry the artifact and soak in 100% isopropyl alcohol, for about 20 minutes. This will help draw out more water from the fabric. Dry thoroughly, and seal with a paste wax, well rubbed in.

With very prolonged soaking the metal fabric can become weakened.
Prolonged soaking is months rather than days or weeks., though for
a very small object this "risk" period should be considerd to be shorter.


Benzotriazole

This is used by restorators and museum preservers.

What is?where do I get it? How do I use it?


BENZOTRIAZOLE = C6H5N3
ATTENTION !!! Benzotriazole is suspected of being a carcinogen. Don't inhale it. Wear gloves and eye-protection.
Only use it in an AIRED room. Wash your hands carefully. Wipe off your artefact carefully to remove all excessed benzotriazole.

Benzotriazole is a solid. Only use benzotriazole in the cleanest form. This is expensive, but has the best results.
Store the benzotriazole - ethanole solution in a light-tight vessel. Otherwise it will reduce.

Benzotriazole is available from artcraftchemicals.com in the States.
I don't know where to get it in the UK. If you know, please tell me

[gameoftag]

Thanks PhotoRob06:
I will research this and decide if i should do this. The last thing i want to do is make things worse, but if all this is true, doing nothing will make things worse. This is a tough call for me. Any other input would be helpful. Has anyone used this method, and if so, what were the results? I appreciate all the advice and info.