Cleaning old coins might seem like a good way to revitalise the appearance of a treasured item, but could in fact reduce a coin's value significantly, and should be avoided. Particularly in the case of old precious metal coins, cleaning them is most definitely not recommended!
Even though it's counterintuitive, you should never clean a coin, as it can significantly reduce its value. Even coins that have substantial dirt, tarnishing, or toning should be kept in their original condition.
The value of silver bullion coins and bars should not be affected by tarnishing.
Don't clean your coins! Not only does this cut their value by as much as half (or possibly even more), but it will be an immediate deal-breaker for many dealers who would've otherwise wanted to buy your coins if only they were left in their original condition.
Before cleaning old coins, consider that appraisers and coin experts suggest not cleaning collectible coins yourself because the coins may lose their value. Using chemical cleaners or scrubbing the coins can leave behind scratches and marks, easily seen by a skilled coin appraiser.
Most Cleaning is Destructive: It Can Literally Change the Surface of a Coin. Any cleaning that requires rubbing leaves microscopic scratches. They are not apparent to the naked eye, but a collector will see them. A collector will look for them.
Distilled water is recommended as tap water contains chlorine. The coin is dipped into olive oil which according to Hudgeons, works best for common copper or bronze coins.
The value of silver has historically increased over time, so keeping your coins for a longer period may result in a greater return on investment. On the other hand, if you have a short-term need for cash, cashing in your silver coins may be the best option.
First, if you think your coins might be of any value, do not clean them at all, since you can possibly damage them by soaking in cleaners like vinegar. If you want to clean the coin for some other reason, vinegar should work fine.
Since it was first produced and sold in the United States in the mid-1800s, baking soda has been a popular product with many useful purposes. One of these is to clean certain valuable items in a safe, effective way. As for whether or not baking soda damages silver coins, the short answer is typically no.
Simply pour the coke into a bowl and submerge your silver into it. The acid in the coke will quickly remove the tarnish. Keep an eye on it – just a few minutes should be enough. Rinse with warm water and dry carefully with a soft cloth.
1. The most important thing NOT to do is clean your coins. Cleaning rare numismatic coins will significantly reduce their value – plain and simple. Although you don't lose much by cleaning a coin which derives value only from its silver content, it's not worth the risk.
Distilled water: Distilled water is best for cleaning silver coins and bars because it does not contain minerals that can leave marks on the surface. Baking soda: Baking soda is a natural cleaner used to clean tarnished silver coins and bars.
The combination of light scraping, soaking in oil and rubbing with fabric basically removed this sludgey coating. Since WD-40 is volatile (and not cheap) I sprayed just enough to cover the coin in a porcelain screw-cap container. The final result is shown. The little brownish spots are what is left of the coating.
Never use metal polish or acid dip to clean your coins! Using these chemicals will cause abrasions or chemical reactions with the metal, permanently damaging your coin. This damage can never be fixed or undone. Additionally, these chemicals can be caustic and cause injury or even death.
If you want to go ahead and clean corrosion off of your old coins, baking soda likely is the safest route to follow. Wet the affected coin with clean tap or distilled water, roll in baking soda, then gently scrub with a soft toothbrush.
The salt and acetic acid in vinegar do the trick. Hot sauce, like Tabasco or taco sauce, also will remove the oxides off pennies. As in ketchup, salt and vinegar are both in hot sauce. Coke and off-brand colas will quickly remove the tarnish.