5 Simple Steps to Clean Dirty Coins * flexco.com

Cleaning money coins is not specifically a difficult task to do. However, depending on the number of coins needing to be cleaned, it can be time-consuming. Coins can be cleaned by mechanical or chemical processes. Mechanical cleaning methods involve some form of friction, and chemical cleaning methods involve a chemical reaction. The cleaning method chosen depends on how dirty the coins are and how delicate they are. Furthermore, it is important to make sure that cleaning methods used are acceptable to numismatists (coin collectors).

For example, if the coins are very dirty, a mechanical cleaning method, such as brushing or ultrasonic cleaning, may be necessary. If the coins are delicate, a chemical cleaning method, such as soaking in a mild acid solution, may be a better choice. Ultrasonic cleaning is a method of cleaning coins that uses high-frequency sound waves to agitate the cleaning solution and remove dirt and debris from the coins.

No matter which cleaning method is chosen, it is important to first test the method on a few coins that are not valuable. This will help to ensure that the cleaning method does not damage the coins. Once a cleaning method has been chosen, it is important to follow the instructions carefully. Cleaning coins improperly can damage them, so it is important to take your time and do it right. Additionally, it is important to dry the coins thoroughly after cleaning to prevent them from rusting.

Essential Materials for Coin Cleaning

Cleaning coins requires a meticulous approach to preserve their delicate surfaces while effectively removing dirt and grime. Here are the essential materials you’ll need:

1. Soft Cloths and Gloves

Utilize a soft, lint-free cloth made from cotton or linen for gently wiping coins. Handle coins with cotton gloves to minimize leaving fingerprints or transferring oils from your hands. Wear nitrile gloves if handling chemically treated coins.

2. Liquid Hand Soap

Mild, unscented liquid hand soap is ideal for removing light tarnish and dirt. Avoid using detergent or abrasive soaps, which can damage the coin’s surface.

3. Distilled Water

Distilled water ensures no impurities or minerals are introduced during the cleaning process. Use it to rinse coins after washing and to prepare solutions.

4. Baking Soda

Sodium bicarbonate (baking soda) is an effective and gentle abrasive that removes stubborn tarnish. Create a paste by mixing baking soda with water and apply it sparingly to the affected areas.

5. Toothbrush

Use an ultra-soft toothbrush for gently dislodging dirt and debris from crevices and details. Avoid hard-bristled brushes or toothpicks, as these can scratch the surface.

6. Olive Oil

Olive oil provides a protective layer to coins and helps prevent further tarnishing. Apply a thin coat after cleaning and polishing to preserve the coin’s luster.

Determining the Type of Coin

The first step in cleaning coins is to determine their type. This will help you choose the most appropriate cleaning method. Here are a few tips for identifying different types of coins:

1. Inspect the metal. Coins can be made from a variety of metals, including copper, silver, gold, and alloys. To determine the metal, examine the coin’s color and luster. Copper coins are typically red or brown, while silver coins are white or gray. Gold coins are yellow or orange, and alloys can have a variety of colors.

2. Examine the surface. Coins can have a variety of surface textures, including smooth, matte, and proof. Smooth coins have a shiny surface with no visible texture. Matte coins have a dull surface with a slightly rough texture. Proof coins have a mirror-like surface and are typically very shiny.

3. Check for details. Coins are often adorned with details such as images, inscriptions, and dates. Examine these details closely to determine the coin’s origin and value. You can also use a magnifying glass to get a better look at the details.

4. Refer to a coin catalog. If you are unable to identify a coin on your own, you can refer to a coin catalog. Coin catalogs provide detailed information about different types of coins, including their metal composition, surface texture, and design details.

Coin Type	Metal	Surface Texture
Copper penny	Copper	Smooth
Silver dime	Silver	Matte
Gold eagle	Gold	Proof

Gentle Cleaning Methods for Delicate Coins

Delicate coins, such as those made of silver or copper, require a gentle touch when cleaning. Here are some methods that will help preserve their integrity:

1. Soft Brushes and Cotton Swabs

Use a soft brush or cotton swab to gently remove dirt and debris from the coin’s surface. Avoid using stiff brushes or abrasive materials, as these can scratch the coin.

2. Baking Soda Paste

Create a paste by mixing baking soda with a small amount of water. Apply the paste to the coin using a cotton swab or soft cloth. Let it sit for a few minutes before rinsing the coin thoroughly with distilled water.

3. Non-Abrasive Solvents

Denatured alcohol and acetone are non-abrasive solvents that can be used to remove stubborn dirt and tarnish. However, they should be used sparingly and with utmost care, as they can damage the coin’s surface if used improperly.

Solvent	Use	Caution
Denatured alcohol	Removes dirt and tarnish	Can evaporate quickly, use in a well-ventilated area
Acetone	Removes heavy tarnish and dirt	Strong solvent, use with extreme caution

Always test solvents on a small, inconspicuous area of the coin first to ensure they do not cause any adverse reactions.

After cleaning, rinse the coin thoroughly with distilled water and pat it dry with a soft cloth. Store the coin in a protective capsule or holder to prevent further damage.

Chemical Cleaning Solutions for Tough Stains

Chemical cleaning solutions can be effective for removing tough stains from coins. However, it is important to use the right cleaning solution for the type of stain and the metal of the coin. Using the wrong cleaning solution can damage the coin.

Acids

Acids can be used to remove rust and other stains from coins. However, acids can also damage the coin if they are not used correctly. It is important to dilute the acid with water and to use a soft cloth to apply the solution to the coin. Acids should only be used on coins that are made of copper, silver, or gold.

Bases

Bases can be used to remove dirt and grime from coins. However, bases can also damage the coin if they are not used correctly. It is important to dilute the base with water and to use a soft cloth to apply the solution to the coin. Bases should only be used on coins that are made of copper, silver, or gold.

Solvents

Solvents can be used to remove grease and oil from coins. However, solvents can also damage the coin if they are not used correctly. It is important to use a solvent that is specifically designed for cleaning coins. Solvents should only be used on coins that are made of copper, silver, or gold.

Chemical Solution	Type of Stain	Metal
Acetic acid	Rust	Copper, silver, gold
Sodium hydroxide	Dirt, grime	Copper, silver, gold
Acetone	Grease, oil	Copper, silver, gold

Removing Rust and Oxidation

Many coins are made of metals that are prone to rust and oxidation, which can damage their appearance and value. To remove rust and oxidation, follow these steps:

1. Identify the metal

The type of metal used in a coin will affect the cleaning method. Copper coins can be cleaned with vinegar, while silver coins should be cleaned with a silver polish.

2. Choose a cleaning method

There are a variety of methods for cleaning coins, including:

Soaking in a solution: This is a gentle method that is suitable for most coins. Soak the coin in a solution of distilled water and vinegar or lemon juice for 30 minutes to 2 hours.
Scrubbing with a soft brush: This method is more abrasive and should only be used on coins that are heavily soiled. Use a soft brush to gently scrub the coin with water and a mild dish soap.
Using a chemical cleaner: This method is only recommended for coins that are severely damaged. Use a commercial coin cleaner according to the manufacturer’s instructions.

3. Dry the coin

After cleaning, the coin should be dried thoroughly. Pat the coin dry with a soft cloth or air dry it.

4. Prevent future rust and oxidation

Once the coin is clean, it is important to protect it from future rust and oxidation. Store the coin in a dry, airtight container.

5. Other tips for removing rust and oxidation

Here are some additional tips for removing rust and oxidation from coins:

Metal	Cleaning method
Copper	Soak in vinegar
Silver	Use a silver polish
Brass	Use a brass cleaner
Nickel	Soak in water and ammonia

If the rust or oxidation is severe, you may need to seek professional help. A coin dealer or conservator can clean the coin using specialized methods.

Polishing Techniques to Enhance Shine

Chemical Immersion

Submerging coins in a mild chemical solution can dissolve tarnish and reveal underlying brilliance. Common options include acetone, denatured alcohol, or distilled white vinegar. Soak coins for a few minutes, then rinse thoroughly with water and dry immediately.

Abrasive Rubbing

Using a soft cloth or sponge, gently rub coins with a mild abrasive such as baking soda, salt, or toothpaste. This method requires care to avoid damaging delicate coin surfaces. Start with a light touch and gradually increase pressure as needed.

Ultrasonic Cleaning

Ultrasonic cleaners use high-frequency sound waves to create microscopic vibrations that agitate dirt and tarnish. This is a safe and effective method for most coins, but avoid prolonged immersion or exposure to harsh chemicals.

Electrolytic Cleaning

This technique involves placing the coin in an electrolytic solution and passing an electric current through it. The current generates hydrogen bubbles that help lift dirt and tarnish from the coin’s surface. This is a more advanced method and requires caution to avoid damage or discoloration.

Laser Cleaning

High-powered lasers can vaporize tarnish and other contaminants without damaging the underlying metal. This is a precise and effective method but is typically used for rare or valuable coins due to its high cost.

Professional Coin Grading

For coins intended for grading or collection, professional cleaning services can provide expert care and preservation. These services typically employ advanced techniques such as ultrasonic cleaning, laser cleaning, and specialized chemical treatments to restore coins to their original luster.

Method	Pros	Cons
Chemical Immersion	Effective, easy, inexpensive	Can damage delicate coins
Abrasive Rubbing	Gentle, controllable	Time-consuming, potential for damage
Ultrasonic Cleaning	Safe, effective for most coins	May not remove deep tarnish
Electrolytic Cleaning	Powerful, precise	Requires caution, potential for damage
Laser Cleaning	Precise, effective	Expensive, only for rare or valuable coins
Professional Coin Grading	Expert care, preservation	High cost

Drying Methods for Preserving Coins

After cleaning coins, proper drying is crucial to prevent damage and preserve their value. Here are various drying techniques to ensure your coins remain in optimal condition:

Air Drying

Place the coins on a clean, lint-free cloth and allow them to air dry at room temperature. This method is suitable for mildly cleaned coins and takes several hours to complete.

Paper Towel Drying

Wrap the coins individually in soft paper towels and gently pat them to absorb excess moisture. Repeat the process multiple times until the towels are no longer visibly damp.

Heat Gun Drying

Use a heat gun set on a low setting to blow warm air over the coins. Hold the gun several inches away and move it constantly to avoid overheating. This method is effective for removing moisture quickly.

Silica Gel Drying

Place the coins in a sealed container filled with silica gel packets. The silica gel will absorb moisture from the air, creating a dry environment for the coins. This method takes several days to complete.

Hair Dryer Drying

Hold a hair dryer set on a cool setting at least 6 inches away from the coins. Blow air evenly over the coins to remove moisture. Keep the dryer moving to prevent overheating.

Oven Drying

Preheat an oven to the lowest possible setting (usually 100°F or 38°C). Place the coins on a baking sheet lined with parchment paper and leave them in the oven for 15-20 minutes. Closely monitor the coins to prevent damage.

Acetone Drying

For coins cleaned with acetone, immerse them in a bath of acetone for a few seconds. Then, quickly remove the coins and gently pat them dry with a lint-free cloth. This method is highly effective but should only be used as a last resort and with extreme caution due to the flammability of acetone.

Protective Coatings to Shield Coins from Damage

Preserving the pristine condition of valuable coins is a top priority for collectors and enthusiasts. Protective coatings offer an effective means of safeguarding coins from environmental factors and damage. Here’s a comprehensive guide to various coatings available:

Acrylic Lacquer

A clear, non-yellowing coating that provides UV protection and resistance to scratches and chemicals. It’s often used for modern coins and proof sets.

Cellulose Nitrate

A traditional coating that creates a thin, waterproof barrier. It’s commonly found on older coins but is susceptible to yellowing over time.

Microcrystalline Wax

A soft, flexible coating that offers protection from moisture and corrosion. It’s ideal for coins with intricate details or matte finishes.

Paraloid B-72

A synthetic polymer coating that provides UV protection and resistance to tarnishing. It’s frequently used on ancient coins and artifacts.

Renaissance Wax

A blended wax coating that provides a high-gloss finish while protecting from fingerprints and oxidation. It’s suitable for both modern and antique coins.

Silicon Dioxide

A hard, durable coating that creates a barrier against wear and corrosion. It’s often used on high-value coins and bullion.

Teflon

A non-stick coating that offers exceptional protection from moisture and dirt. It’s mainly used to seal the rims of coins in coin holders.

UV Stabilizers

These additives can be incorporated into protective coatings to enhance their resistance to ultraviolet radiation, which can cause deterioration over time.

Coating Type	Characteristics
Acrylic Lacquer	Clear, UV protection, scratch resistance
Cellulose Nitrate	Waterproof, traditional
Microcrystalline Wax	Soft, moisture protection
Paraloid B-72	UV protection, tarnishing resistance
Renaissance Wax	High-gloss, fingerprint protection
Silicon Dioxide	Hard, wear resistance
Teflon	Non-stick, moisture protection
UV Stabilizers	Enhanced UV protection

Legal Considerations for Coin Cleaning

Cleaning coins can have legal implications, depending on the type of coin and the method used. It is important to be aware of these laws to avoid potential consequences.

Federal Laws

The following federal laws apply to coin cleaning:

– **The Coinage Act of 1965** prohibits the mutilation, disfigurement, or alteration of U.S. coinage.
– **The Hobby Protection Act of 1973** prohibits the sale or possession of counterfeits or altered coins.

State Laws

Some states have their own laws regarding coin cleaning, typically focusing on cleaning methods that damage or alter the coin’s surface:

– Many states prohibit the use of harsh chemicals or abrasive materials on coins.

Exceptions

Exceptions to the Legal Considerations

There are some exceptions to the legal restrictions on coin cleaning:

– **Cleaning to remove dirt or debris:** It is generally acceptable to clean coins to remove dirt or debris, provided that it is done with non-damaging methods.
– **Cleaning to preserve the coin:** In some cases, cleaning may be necessary to preserve the coin from damage, such as in the case of a coin that is heavily tarnished.
– **Cleaning by authorized individuals:** Certain individuals, such as museum curators or professional numismatists, may be authorized to clean coins under specific circumstances.

Recommended Coin Cleaning Methods

If you decide to clean a coin, it is important to use non-damaging methods:

Soft cloth: Use a soft cloth to gently wipe away dirt or debris.
Mild soap and water: In some cases, you can use mild soap and water to clean coins. Use a soft brush to gently scrub the coin, and rinse thoroughly with water.
Acetone: Acetone can be used to remove dirt and tarnish from coins, but it should be used with caution as it can also remove the coin’s patina.

Avoid the following methods as they can damage the coin:

Harsh chemicals: Do not use harsh chemicals, such as bleach or ammonia, to clean coins.
Abrasive materials: Do not use abrasive materials, such as steel wool or scouring pads, to clean coins.
Ultrasonic cleaners: Do not use ultrasonic cleaners to clean coins, as they can damage the coin’s surface.

Storage and Display Best Practices for Coin Collections

Proper Storage

Coins should be stored in a dry, cool, and dark place to prevent corrosion and tarnishing. Avoid storing coins in areas with fluctuating temperatures or humidity, as this can cause condensation and damage the coins over time.

Coin Albums

Coin albums are a great way to organize and protect your collection. Choose coin albums made with archival-quality materials, such as acid-free PVC-free plastic. Each coin should be stored in its own pocket to prevent scratching and contact with other coins.

Tip	Benefits
Use archival-quality materials	Protects coins from damage
Store coins in a dry, cool, and dark place	Prevents corrosion and tarnishing
Handle coins with gloves	Prevents fingerprints and oils
Avoid displaying coins in direct sunlight	Prevents fading and tarnishing
Use coin capsules or coin albums to organize and protect coins	Provides individual protection and prevents scratching

How to Clean Money Coins

Coins can become dirty and tarnished over time, but there are a few simple ways to clean them and restore their shine. Here are a few methods you can try:

Soap and Water: This is the most basic method and is effective for removing dirt and grime. Simply soak the coins in warm soapy water for a few minutes, then use a soft cloth to gently rub away any remaining dirt. Rinse the coins thoroughly with clean water and pat them dry.
Baking Soda: Baking soda is a mild abrasive that can help to remove tarnish and dirt. Make a paste of baking soda and water, and apply it to the coins. Rub the paste gently with a soft cloth, then rinse the coins thoroughly with clean water and pat them dry.
Vinegar: Vinegar is a mild acid that can help to dissolve tarnish and dirt. Soak the coins in vinegar for a few minutes, then use a soft cloth to gently rub away any remaining tarnish or dirt. Rinse the coins thoroughly with clean water and pat them dry.
Commercial Coin Cleaner: There are also a number of commercial coin cleaners available that can be used to clean coins. These cleaners are typically formulated to be safe for use on coins, and they can be effective at removing tarnish and dirt. Follow the instructions on the product label carefully.