Don't clean it!

[cptbil]

If you ever want to sell it !
Don't ever scrape or clean anything !

If you Do!
You'll destroy it's valve!
It will become unsaleable or you'll get a lot less for it,


Leave that to the professionals !

example:
Just how many nice shining, dated items have you seen in a Museum ?

[Michigan Badger]

I've found that a water soak is good for most dug copper/bronze finds. It removes the surface crud without giving the item that artificial cleaned look.

But I think I know what you're saying, harsh cleaning is oft times a very bad thing.

Large cents, Colonial coppers, etc., cleaned via electrolysis and/or acids look awful. They're all pitted and nasty looking. A dug large cent with a smoother corrosion and faint detail is far more desireable to a collector than one that looks like it sat inside a car battery for 6 months but has deep detail.

I know this is not accepted on here but it's true. But today we have a strange thing going on with ebay and some who don't know what they're doing bid high on crap coins. They'll be in for a shock when they try to sell to a real collector some day.