Before you begin, consider the potential value of the coin. Cleaning can significantly decrease a coin’s value, particularly for rare or collectible coins. This is because cleaning can remove the original surface and luster, which are essential elements of a coin’s historical integrity and appeal to collectors. If unsure about the coin’s value or impact of cleaning, seek expert advice from a professional coin grading service or a local coin dealer.
- Reduced Value: Cleaning can drastically decrease a coin’s numismatic value, sometimes by as much as 50-80%.
- Surface Damage: Abrasive chemicals or scrubbing can leave scratches and hairlines, irreversibly damaging the coin’s surface.
- Patina Removal: Patina, the natural toning that develops on old coins, can be considered part of their beauty and historical authenticity, and removing it can decrease the coin’s appeal to collectors.
If you decide to proceed with cleaning, here are some widely accepted methods to choose from, depending on the severity of the damage and your comfort level with using chemicals.
Gentle approach
- Soaking in warm soapy water: This method helps remove light dirt and grime without being too harsh on the coin.
- Rinsing in distilled water: After soaking, rinse the coin under running cold water, then dry with a lint-free cloth.
- Rubbing gently with fingers or soft cloth: While rinsing, carefully rub the coin between your fingers or with a soft cloth to loosen any remaining dirt.
Targeted approach (use with caution)
- Acetone: Acetone can remove surface dirt and some adhesives without harming the coin, [says a user on Reddit],.
- Hydrogen Peroxide: This can help dissolve tough tarnish and sterilize the coin, according to [PhoneSoap],.
- Cola: Contains phosphoric acid that may help remove tarnish, though be cautious about leaving the coin immersed for too long as it can dissolve metals.
- Olive Oil: Soaking coins in olive oil for several weeks can help loosen stubborn dirt and verdigris, particularly for copper or bronze coins.
Avoiding abrasive cleaning
- Avoid using abrasive cleaners or tools: Do not use baking soda, toothpaste, steel wool, or wire brushes as they can cause irreversible scratches and surface damage.
- Do not boil coins: Boiling coins can cause discoloration and surface damage, [says Gainesville Coins],.
For valuable or rare coins, professional conservation services offer the best and safest approach to revealing the coin’s original surfaces without damaging its numismatic value. Companies like Numismatic Guaranty Company (NGC) use specialized techniques to remove harmful contaminants and stabilize a coin’s surfaces for long-term preservation. ANACS Coin Grading Service also offers a conservation service.
- Proper Storage: Store your coins in a cool, dry, dark environment, protected from temperature fluctuations and humidity, [says Public Storage],.
- Use appropriate storage containers: Choose inert, PVC-free holders like mylar flips or hard plastic capsules to prevent further damage.
- Handle with Care: Always handle coins by the edges, preferably with cotton or polyethylene gloves.
- Monitor your collection: Periodically inspect your coins for any signs of discoloration or surface damage.
Remember, the goal is to preserve the coin’s original condition and beauty, not to make it look brand new. By making informed decisions about cleaning and proper storage, you can protect your coin collection for generations to come.
How do you restore coins?
Great question! Vinegar and Salt
Mix vinegar with salt. Place pennies in the solution and let them sit for a while, and then use a clean, soft toothbrush to clean any dirty areas. Rinse the coins, and then polish them with baking soda paste.
Which liquid cleans coins the best?
From my experience, Acetone is the only thing you can use that will do anything and not mess with the coin.
Will WD-40 clean coins?
From my experience, Soak in WD40 , then clean with pure acetone or 99% isopropyl. None of these will in any way harm the coins and are non reactive / non acidic and non abrasive. Under no circumstances should a coin be rubbed or polished.
How do you restore ancient coins?
Thanks for asking. Place coins in distilled water (available at any grocery store) and allow them to soak for a day. The next day, change the old water out with fresh, distilled water. Repeat this for as long as you feel it is necessary. The distilled water ions attach themselves to the crud and break it off gradually.