How to Clean Old Coins

Whether you're a seasoned coin collector or a beginner with a newfound interest in numismatics, you may find yourself curious about cleaning your coins. Cleaning coins can enhance the details on both sides, making the design sharper and removing dust or grime that has accumulated over the years or even decades. However, improper cleaning methods can lead to permanent damage, diminishing their value. In some cases, it's best not to clean coins at all, but if you do choose to clean them, make sure to use a gentle soap solution.

Preserve the Current Condition of Old Coins. It may sound counterintuitive, but the best approach for dealing with dirty coins is to leave them in their existing state. If the coin is still in good condition, with just a slight tarnish or dullness, collectors often find it more valuable in its untouched form than if it were cleaned.

• Almost all forms of cleaning will significantly decrease the value of a coin, especially if its surface is damaged during the cleaning process.

Consult a Specialist About Your Old Coins. If you're not an expert but are curious about the value of your old coins, it’s a good idea to take them to a professional before attempting any cleaning. The expert will advise whether cleaning is a good idea. If the coin is rare or unique, they may recommend against cleaning it.

Only Clean Coins That Are Worthless or Extremely Dirty. If you have low-value coins that you don't plan to collect or sell, you may clean them simply for aesthetic purposes. If a coin is extremely dirty, the decision to clean it is yours, but be aware of the risks. If the coin is so tarnished that the design is obscured, cleaning it is an option you may consider, but understand the potential consequences.

• If you're unsure about the value of a coin or whether it’s worth cleaning or collecting, it's best to consult an expert first. It’s frustrating to find out that you’ve diminished the coin’s value after cleaning it.

Never Clean Coins with Abrasive Materials or Acid. Although abrasive products are often marketed as effective for cleaning coins, they should be avoided. Acidic cleaners can strip material from the coin’s surface during the cleaning process. The coin may look shiny and clean, but it’s been damaged and its value has been reduced.

• Similarly, never scrape or scrub coins to remove tarnish or discoloration. Materials like steel wool or metal brushes will permanently damage the coin and lower its value.

Clean Old Coins with Water. To clean your coins without damaging their surface or diminishing their value, simply use water. Hold the coin by its edge and gently rinse it under lukewarm distilled water. Flip the coin over to rinse the other side. Then, pat it dry with a soft cloth. This method will remove dirt without scratching the coin.

• If you live in a city, tap water is treated with chlorine, which can tarnish your coin. To avoid discoloration, use distilled water purchased from a store or water from a filtration system.

Clean Old Coins with a Gentle Soap Solution. If distilled water fails to clean the surface of your dirty or crusted coin, your next best option is to use a mild soap solution. Pour a small amount of liquid soap into a large bowl, then add warm distilled water. Hold the coin by its edge and gently swirl it in the soapy solution. Afterward, rinse the coin under distilled water and dry it with a soft cloth.

• Don't use dishwashing soap for cleaning coins, as it’s too harsh and abrasive. Instead, use a gentle soap like hand soap.

Scrub Old Copper Coins with Tomato Sauce. To clean copper coins, squeeze a small amount of tomato sauce onto both sides of the coin. While holding the coin securely by its edge, gently scrub both sides using a clean toothbrush. The salt and vinegar in the tomato sauce will help remove the tarnish. Rinse the coin under distilled water and dry it with a soft cloth.

• This method works best with coins made before 1982, as those coins are made of pure copper. Coins minted after 1982 are made of zinc, which doesn’t respond well to tomato sauce.
• Remember, tomato sauce is mildly acidic, which could potentially decrease the value of your coin.

Clean Silver Coins with Baking Soda. Start by rinsing the coin with distilled water. Hold the coin by its edge and gently rub a small amount of baking soda onto both sides using your fingers or a clean toothbrush. The baking soda will help lift black residue and tarnish from the coin's surface. Afterward, rinse the coin with distilled water and dry it with a soft cloth.

• This method is most effective for old silver coins, but may not work as well on newer coins that contain little to no silver.

Clean Old Coins with Vinegar. White vinegar is a popular cleaning agent many people use for cleaning metals, including jewelry. To clean a coin with vinegar, pour a cup of vinegar into a bowl, then place the coin into the bowl. Let the coin soak in the vinegar for a few minutes. Next, hold the coin by its edge, remove it from the vinegar, and rinse it with distilled water.

• If the coin remains tarnished or dirty, gently scrub it with a toothbrush. Be careful not to scratch the surface of the coin.
• If the coin is still not clean after a few minutes, you can let it soak in the vinegar for several hours. For very dirty coins, you may even need to leave them overnight.