Corrosion Removal

SteveB 21 years ago

I found some old pennies by an old spring this weekend. One is a 1917S wheat penny. The ground they came out of was highly mineralized. On their surfaces, the pennies have black oxidation.

Is there a way to take off this corrosion? I really don't want to use any chemicals, as it may eat at what copper is left.

I have seen programs on TV where old coins found in shipwrecks are cleaned electrolytically by passing a small current through them.

Does anyone know how to do this, or can steer me in the right direction?

Steve

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Bugs 21 years ago

Coin collectors use olive oil or mineral oil to clean up dirty coins. If you want to try reverse plating, use a copper sheet anode in a plastic bucket. A 12 V battery charger and a tbsp of sodium carbonate [washing soda], or sodium bicarbonate/ gallon for electrolyte.As I remember, the positive goes to the copper anode, but I could be wrong. I've had limited success on rusted steel tools using an iron anode. bugs

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Jeff R 21 years ago

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Just remember - most coin collectors will tell you that cleaning destroys a coin's appeal. Don't worry, though. Your wheaties are worth less than a buck, anyway:

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HTH

-- Jeff R.

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Dave Hinz 21 years ago

Nope.

Keep 'em as is. Any attempt to clean them will make them worthless. The surface is part of the history of the coin. A 1917S isn't a key date, but it's still not something you'd want to damage by cleaning.

Dave Hinz

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fredfighter 21 years ago

direction?

rec.collecting.coins would be the right direction I should think.

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Ted Edwards 21 years ago

Noting the advice to not clean them, if you decide to do it anyway, here's how I'd do it.

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Ted

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