How to Clean Metal Detecting Finds: Preservation and Restoration Tips

Metal detecting is a fascinating pastime that can reveal everything from rare coins to rusted artifacts. But once you’ve pulled something special from the ground, knowing how to clean and care for it is key. This book offers practical guidance on how to clean, conserve, and restore your discoveries safely.

Assessing the Find: Know What You’re Dealing With

The first step in cleaning a metal detecting find is properly assessing it. Not every item requires the same approach, so understanding the material and condition of the find will help you determine the best course of action. Here’s what to look for:

Material Identification: Is your find made of iron, copper, silver, gold, or another metal? Each material reacts differently to cleaning methods, and certain metals require more delicate treatment. For example, copper and bronze can develop a green patina over time, which is often valuable and should be preserved, while iron may rust and require a different approach to cleaning.
Age and Historical Significance: Older items, particularly those of historical or archaeological significance, often require more care than modern objects. Artifacts such as ancient coins, relics, or jewelry can lose their authenticity or value if scrubbed too aggressively. In such cases, leave the item as is or perform only minimal cleaning to preserve its historical integrity.
Corrosion and Condition: Assess the find’s condition—does it show signs of corrosion or heavy dirt buildup? Items with heavy corrosion, especially those made of iron or steel, require a gentler approach to prevent further deterioration. It’s also important to determine if the object is fragile. Fragile finds, such as delicate jewelry or worn coins, may require professional conservation instead of DIY cleaning.
Inscriptions and Details: If your find includes inscriptions, markings, or intricate details, cleaning should be approached cautiously. Heavy scrubbing or chemical cleaning might erase important information. In some cases, it’s better to preserve the patina intact to maintain the originality of the markings.

Key Takeaway: Before cleaning, always take the time to carefully assess your find’s material, age, condition, and historical significance. A well-considered approach ensures that the cleaning process doesn’t accidentally diminish the value or integrity of your discovery.

Safe Cleaning Methods for Common Metals (Coins, Jewelry, Relics)

Once you’ve identified the type of metal your find is made of and assessed its condition, it’s time to clean it—if cleaning is necessary. Different metals require different methods to ensure that the cleaning process doesn’t damage the item. Here’s a guide for safely cleaning common metals found during metal detecting:

Iron (Rusty Relics and Tools)

Iron objects are among the most common finds but are also prone to rust and corrosion. When cleaning iron, it’s essential to be gentle and avoid aggressive scrubbing.

Method: Soak the item in distilled water to loosen dirt and rust. Let it sit for several hours or overnight.
Tools: After soaking, use a soft nylon brush or toothbrush to remove dirt and rust gently. For heavy rust, use a fine steel wool pad, but apply it lightly to avoid damaging the surface.
Important Tip: For heavily rusted items, consider using electrolysis for a deeper clean. This method involves submerging the item in a solution of water and washing soda, followed by using a battery charger to reverse the corrosion process. Electrolysis should be performed with caution and is best suited for more experienced detectorists.

Copper and Bronze (Coins, Relics, Jewelry)

Copper and bronze items are often found in the form of coins, jewelry, or historical artifacts. These metals can develop a greenish patina over time, which many collectors prefer to leave intact as it adds character. However, if cleaning is necessary:

Method: Mix water and baking soda (or, for a more powerful clean, combine salt and lemon juice). Gently apply the mixture to the object with a soft cloth or toothbrush and rub in tiny circular motions.
Tools: Soft toothbrush or a microfiber cloth.
Important Tip: Avoid using abrasive materials, as they can scratch or damage the surface. For heavily tarnished copper or bronze, consider using a mild acid, such as vinegar, to break down the tarnish. However, do not soak the object for long periods; monitor the progress closely.

Silver (Coins, Jewelry, Relics)

Over time, silver can tarnish, especially when exposed to moisture and air. Luckily, silver items are relatively easy to clean, but be careful not to remove too much of the tarnish if you want to preserve their antique look.

Method: Soak silver items in warm, soapy water, using mild dish soap. After soaking, gently wipe the item clean with a soft cloth.
Tools: Soft cloth, toothbrush (optional).
Important Tip: For tarnished silver, you can create a simple cleaning solution using aluminum foil, baking soda, and warm water. Place the silver item in the solution for a few minutes. The chemical reaction will help lift the tarnish without causing damage.

Gold (Jewelry, Coins, Artifacts)

Gold is one of the most resilient metals, but it still requires care when cleaning. Since it is softer than many other metals, you should avoid abrasives that might scratch its surface.

Method: Gently rinse gold items in warm, soapy water. To avoid damaging any fine details or settings, carefully wipe up dirt with a soft cloth or toothbrush.
Tools: Soft cloth, toothbrush (optional).
Important Tip: For stubborn dirt or grime, a jewelry cleaning solution specifically designed for gold can be used; however, avoid soaking gold for extended periods in harsh chemicals.

Aluminum (Modern Relics, Buttons, Rings)

Aluminum items are lightweight and often used in modern products, such as buttons or rings. However, aluminum can oxidize, which might affect its appearance.

Method: Soak aluminum items in warm water and a small amount of mild detergent. Gently scrub with a soft brush.
Tools: Soft brush, microfiber cloth.
Important Tip: Aluminum can be easily scratched, so avoid using abrasive materials or too much pressure while cleaning.

Nickel (Coins, Relics)

Nickel-plated objects can tarnish over time, often appearing dull or tarnished. Cleaning nickel-plated items can be challenging because excessive polishing can strip the plating.

Method: A gentle wipe with a soft, damp cloth dampened with distilled water is usually sufficient to remove dirt. For tarnished nickel, use a paste of baking soda and water to buff the surface gently.
Tools: Soft cloth, soft-bristled brush.
Important Tip: Avoid abrasive cleaning methods or chemicals that may cause the nickel plating to wear off.

Key Takeaway: When cleaning metal detecting finds, always tailor your method to the specific metal you’re working with. Gentle, non-abrasive cleaning is generally recommended, especially for historical or valuable artifacts. Always test methods on less valuable items first to gauge how the metal reacts to different cleaning approaches.

When to Leave It Alone: Items That Shouldn’t Be Cleaned

While cleaning your finds can be tempting, some items are better left as they are. Overzealous cleaning can diminish the value, historical significance, or natural beauty of certain objects. Here’s when it’s best to leave your find untouched:

Historical Artifacts and Coins

For many historical items, especially ancient coins or relics, the original surface and patina are integral to their authenticity and value. Cleaning these items could strip away important details, inscriptions, or historical clues. Some collectors even prefer to keep the natural corrosion and dirt, as it adds character and confirms the item’s age.

Items with Delicate Patina

Metals like copper and bronze often develop a green or brown patina over time. While this may appear to be tarnish to the untrained eye, it’s actually a protective layer that can prevent further corrosion. Cleaning off this patina can permanently damage the item, causing irreversible harm.

Very Fragile Finds

Some finds, especially those that are particularly old or delicate (such as thin gold leaf or worn glass), can be easily damaged by even gentle cleaning. If an item is fragile, it’s often best to leave it as-is or consult a professional conservator for advice.

Organic Finds (Wood, Leather, Bone)

If your metal detecting haul includes organic materials such as leather, wood, or bone, cleaning them can be incredibly risky. When these materials are exposed to chemicals or moisture, they are more likely to distort, crack, and deteriorate. Any cleaning should be done with extreme care and, ideally, by a conservation specialist.

Items with Strong Historical Value

If you suspect your find is a rare or historically significant item, it’s often best to consult an expert. In some cases, cleaning it yourself can lower its market value or destroy information that would be valuable for research or restoration. Museums, archives, or professional conservators can provide guidance on how to properly care for and preserve the item.

Key Takeaway: Sometimes, the best way to preserve your finds is to leave them in their original state. If an item has historical value, a delicate patina, or is fragile, consider preserving it without cleaning. Always err on the side of caution and consult experts when in doubt.

Homemade vs. Professional Solutions: What Actually Works

When it comes to cleaning metal detecting finds, numerous DIY solutions are available, but not all of them are equally effective or safe. While homemade methods can be cost-effective and accessible, professional solutions are often more reliable and designed to preserve your items in the long run. Let’s take a closer look at both options:

Homemade Solutions: Simple, But Risky

Many metal detecting enthusiasts swear by homemade cleaning methods, often utilizing common household items such as vinegar, baking soda, or lemon juice. These can be effective in certain situations, but they also carry risks.

Vinegar & Lemon Juice: Both of these acids are popular for cleaning tarnished metal, especially copper and bronze. They can help remove dirt, oxidation, and grime quickly. However, prolonged exposure can strip the metal’s patina or cause unwanted corrosion, especially for delicate finds like coins or jewelry. Always test these methods on less valuable items first, and never soak items for too long.
Baking Soda Paste: This gentle abrasive can be useful for cleaning tarnished silver or copper. It’s typically mixed with water or vinegar and applied with a soft cloth or toothbrush. While it works well for removing dirt, it can also scratch the surface if used too aggressively. It’s best for lightly tarnished or modern items, not historical pieces.
Electrolysis (DIY Method for Iron): This process involves using a battery charger, water, and washing soda to reverse the effects of corrosion on iron items. It can be very effective for heavily rusted relics and tools, but it requires careful monitoring to prevent over-cleaning. DIY electrolysis can also be difficult for beginners, and improper use could damage the item.
Dish Soap & Water: For items that need a basic cleaning, soaking in warm soapy water is an excellent and safe method. It’s gentle enough for most metals and works well to loosen dirt without causing harm. However, be cautious not to use hot water, as it can cause some metals, especially copper and bronze, to tarnish more quickly.

Professional Solutions: Safe, Effective, and Long-Term Care

While homemade solutions can offer quick fixes, professional products and services are often the best choice for preserving the integrity of your finds.

Ultrasonic Cleaners: Professional-grade ultrasonic cleaners use sound waves to remove dirt and debris from the surface of your finds without damaging the metal. This technique works very well for delicate objects like jewelry, coins, and tiny artifacts. While ultrasonic cleaning is gentle, it’s essential to select a cleaner suitable for the type of metal to prevent accidental damage.
Conservation Chemicals: Professional conservation chemicals are available for items that require deeper cleaning or restoration. These are specially formulated to clean metals while minimizing the risk of damage. For example, a professional conservator might use a corrosion inhibitor or specific acid solutions to carefully clean iron objects without stripping their patina.
Electrolysis (Professional Method): While DIY electrolysis can be tricky, professional conservators can use this method with precision to clean heavily corroded items. The equipment used in professional settings is more controlled, ensuring a safer and more effective outcome without risking damage.
Consulting a Conservator: If you have a particularly valuable or fragile item, consulting a professional conservator may be the best choice. They have the expertise and equipment to clean, restore, and preserve historical artifacts and delicate finds in a way that ensures long-term protection.

Key Takeaway: Homemade methods are accessible and can be effective for simple cleaning tasks, but they also carry risks. For valuable or delicate finds, it’s often best to invest in professional solutions or consult an expert. When in doubt, professional care ensures your items are cleaned safely and preserved for years to come.

Preservation and Storage Tips to Prevent Future Damage

Once your item is clean, it’s time to protect it:

Dry Thoroughly Before Storing: After cleaning, make sure everything is thoroughly dry to avoid rust or tarnish. Use a soft cloth or a low-heat hairdryer to dry the area gently.
Use Anti-Tarnish and Anti-Rust Solutions: Apply microcrystalline wax or anti-tarnish solutions, such as Renaissance Wax, to create a protective barrier for metals prone to tarnishing.
Store in Acid-Free Containers: To prevent degradation from acids in regular plastics, use archival-quality, acid-free storage materials, such as Mylar bags or polyethylene boxes.
Control Temperature and Humidity: Store finds in a stable environment with temperatures around 60-70°F (15-21°C) and humidity levels at 40-50%. Use desiccants if necessary.
Display with Caution: When displaying, use UV-protective glass and avoid direct sunlight. Ensure items don’t touch the glass to prevent scratches.
Avoid Cleaning Too Often: Clean finishes only when necessary to preserve their patina and prevent surface damage. Minimize handling and exposure to dirt.
Label and Document Your Finds: Keep a detailed record of each find, including its discovery date, location, and condition. Use acid-free tags and take photos before and after the cleaning process.

Key Takeaway: Proper storage and preservation ensure your metal detecting finds remain in great condition for years. Store them in controlled environments, apply protective coatings, and handle them with care to maintain their value.

Conclusion

Cleaning metal detecting finds is part science, part art. With the right approach, you can bring out the best in your treasures without harming their integrity or historical value. Take your time, choose the right methods, and enjoy the satisfaction of restoring the past.

FAQs

Can I use household vinegar to clean coins?

Vinegar is acidic and can damage coins if used improperly. It’s better to use distilled water or consult coin-specific methods.

What’s the safest cleaning method for beginners?

For most findings, soaking in distilled water and lightly brushing with a soft toothbrush is a safe starting point.

Should I clean a coin if I want to sell it?

In most cases, no. Cleaning can reduce the value of old or rare coins.

Is it okay to use a metal brush on rusty relics?

Only for heavily rusted iron items; proceed carefully even then. Nylon brushes are safer for most finishes.

How can I tell if a find is valuable?

Look for maker’s marks, unusual shapes, or historically significant features. When in doubt, ask a museum or local expert.