How To Clean Metal Detecting Finds Without Damaging Them

by Chad Eicher

how to clean metal detecting finds

Movies, comic books, and children’s tales are full of images of gleaming buried treasure. A striking contrast to the reality that the earth is full of dirt and other grime. Thus, metal detecting finds are almost always filthy unless dropped only hours before. But using the wrong cleaning method could visibly damage them. 

Cleaning metal detecting finds is not encouraged because it reduces their value and risks damage. Cleaning methods depend on the metal but can include dish soap, mineral oil, vinegar, or electrolysis. Mild abrasives like baking soda make silver shiny but will leave microscopic scratches. 

Many metal detecting finds are not worth much, while others are worth a small fortune. For example, older coins are frequently not worth more than their face value unless they sport a unique minting error or are incredibly rare. Yet, these finds still have novelty value and can be fun to display at home or use as part of a project, such as jewelry making. In these instances, you’ll want to clean your metal detecting finds. 

How To Clean Metal Detecting Finds Without Damaging Them

old coins

Establishing the metal of your metal detecting find before cleaning it is essential. The wrong method could cause visible damage. For instance, copper and water are not a good mix. However, gold jewelry is frequently cleaned with a little warm water and sometimes with a dab of dish soap to make a diamond sparkle. 

All methods have their pros and cons. None of them are a hundred percent guaranteed to cause no damage. Even with the utmost care, there are risks of microscopic damage. However, some methods are safer than others.

Cleaning With Water And Baking Soda

Baking soda is a mild abrasive and thus is a favorite for those seeking an environmentally friendly and inexpensive cleaner. However, it should be used cautiously. It is not advised for most metals, including gold plating and antique silver. However, using it to clean nickel or silver coins of no value will make them shiny. But be aware that there may be microscopic scratches left behind. 


  • Inexpensive
  • Effective


  • Unsuitable for most metals
  • It may leave microscopic damage

Cleaning With Dish Soap And Water

Gentle dish soap, such as Dawn, can be used to clean many finds, but avoid it for copper or brass. Do not use dishwasher soap, as it is too abrasive. 

Ideally, you want to use a polishing cloth. But if you need a brush, select a very soft toothbrush. 


  • Inexpensive
  • Makes many objects shiny


  • Won’t remove rust
  • Doesn’t remove most tarnish
  • It can’t be used for copper or brass

Cleaning With Vinegar

Soaking and cleaning with vinegar is suitable for most metals. Removing all the vinegar once finished is essential, as prolonged contact could cause damage. Ideally, if you need to rub rather than soak, use a polishing cloth or a very soft toothbrush. Always try the cloth before the brush, as any toothbrush risks unseen damage. 

Adding ionized salt is a favorite of many. However, be aware it increases the chances of microscopic damage. 


  • Gentle
  • Inexpensive


  • It can take a long time
  • Must be monitored carefully
  • Will not remove major gunk

Cleaning With Ultrasonic

Ultrasonic is a gentle way to clean many types of metal. It is essential to monitor the process, as leaving items in for prolonged periods can cause damage. You can make your own ultrasonic or buy a unit ranging from under fifty bucks to over five thousand. The larger the cleaning device, the more likely it is to cause damage to older, more fragile items. 

Objects with a jewel that contains a fracture can be harmed. In addition, porous items such as pearls should never be put in the ultrasonic cleaner. Lastly, ensure the solution or additives, such as dish soap, are compatible with the metal.  

To reduce electricity bills, some people soak their find in pre-heated vinegar for 24 hours before placing it in the ultrasonic. 


  • Gentle
  • Nonabrasive


  • Units can be pricy
  • Can cause high electricity bills for larger units to run for a long time
  • Must take care that the solution and any additives won’t harm the object

Cleaning With Renaissance Wax 

Renaissance wax is a clear polish made from microcrystalline wax. It cleans the item and leaves behind a clear, protective layer that prevents future tarnishing (other waxes leave a visible or discoloring layer). The wax is suitable for various materials, including wood and metals like copper. 

The price of the wax isn’t too expensive, but it adds up over time. It also requires some effort to use. It is beloved by many who work in museums, those with collectible swords, and hunters maintaining knives or restoring older rifles. Thus, it is excellent for coins. 


  • Used by museums
  • Safe for items not used to serve food
  • Prevents most future tarnish


  • Using it regularly can be expensive
  • It can require time and effort to apply properly
  • The smell is initially strong but will dissipate 

Cleaning With A Rock Tumbler

Rock tumblers are an old favorite of metal detectors to clean their finds. However, they will almost certainly leave microscopic damage. In addition, it is recommended to avoid tumblers that have been used for rocks, as microscopic debris from the stones can be left behind and be abrasive to metal. 

To use, ensure the coins placed inside are of the same metal. In addition, it’s best to group them with the same type of damage. Then use the least damaging solution or material as you can.


  • Pretty fast
  • Easy to use


  • Probably going to damage the item
  • Uses electricity

Should You Clean Metal Detecting Finds?

You should not clean your metal detecting finds if you hope to sell them. They lose value even if they are not damaged in the cleaning process. Collectors and those interested in their history want the “data” the gunk provides. Thus, cleaning metal detecting finds should be reserved only for what you intend to keep. 

If the object is too grimy to identify, use a very soft toothbrush to gently flick away the much. Stop brushing it as soon as it is identifiable. 

Lastly, even the gentlest cleaning methods risk damage. There is no perfect cleaning method that is guaranteed to be harm free. Museums and antique collectors have spent years perfecting the art of cleaning antiques and artifacts with minimal damage. It is unlikely anyone at home can effectively clean an item without causing some minor microscopic marks.


Cleaning metal detecting without damaging them is nearly impossible. Thus, you should leave the grim on any item you hope to sell. If keeping the object for yourself, be sure to use the gentlest method that suits the metal. Also, use the mildest method first and frequently monitor the process.  

Photo of author

Article by

Chad Eicher

Detectorist Chad is passionate about metal detecting since he got his first metal detector as a gift when he was 12 years old. He created Metal Pursuits to share his knowledge and create the ultimate metal detecting resource on the web.

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