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How to Clean Old Coins

Old coins.
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Old coins can become dirty very easily, and over the years build up layer upon layer of grime and dust. When you’re starting a collection of ancient numismatic coins, you might think you need to give each round a thorough cleaning. However, this is not the case. While you might enjoy polishing up some old coins so that they sparkle, you might accidentally reduce the value of your coin. 

Most investors and coin experts would recommend that you never clean old coins. The tarnish, stains, and signs of age all add to the story of an ancient coin and can make it more valuable in fact. If you were to clean a valuable old coin using harsh chemicals, you could inadvertently remove a whole chunk of value. Just like when you’re cleaning gold coins, not accidentally damaging them is the highest priority. So cleaning old coins is a very risky business. 

If you’re certain that it’s a good idea to clean your old coins, then we have a few different options to try out. If you aren’t too worried about the investment or monetary value of your coins collection, then cleaning it is less risky. Assuming your coins hold mainly sentimental value, cleaning them might help you enjoy them more, and perhaps prepare them to display. So, read on to discover everything you know about how to keep your old coins in top condition. 

Should I Clean Old Coins?

If you ask almost any coin expert, they will advise you to never interfere with old and ancient coins. Unless you’re a specialist yourself, there’s no way to know which marks you see on any given coin are superficial, and which add historical significance and value. Old coins are graded by collectors according to their condition, rarity, and many other factors. However, outer dirt won’t affect this grading, so you don’t need to worry about losing out. 

One aspect coin collectors should be aware of when considering cleaning their old coins is that certain processes that happen over time actually increase the value of their coin. Patina is a green film that forms on old metal, we see it very often on ancient silver coins. This coating might seem unsightly, but by coin collectors and numismatics, it’s very much appreciated. If your coin has an oxidized patina coating, you should definitely avoid cleaning it. The majority of the time, removing this layer will significantly devalue your coin. 

If you’re still sure that cleaning your old coins is the right idea, there are a few different options we can recommend. It’s vital that you take the utmost care when cleaning old coins, and follow instructions to the letter. Be as gentle as possible with your cleaning process and always err on the side of caution. Although they may look prettier, shiny and polished coins are often much less valuable than their ancient dirty counterparts. 

A collection of old silver coins.

Old coins should never be cleaned with harsh chemicals.


How to Care For Old Coins 

Before we explain exactly how you can clean different types of old coins, we’ll go over the most important ways you need to take care of them. There are plenty of steps that you can take to preserve the value and condition of your old coins, prevent any further damage from being inflicted on them, and ensure they stay in the best possible shape for the future. Aside from the obvious, which is simply not cleaning your coins at all unless absolutely necessary, here’s how you can take care of your old coins.

  • Never use harsh chemicals or materials to clean old coins: Any cleaning product containing an abrasive, solvent, or acid should never go near to your precious coins. The harsh substances might remove the outer layer of your coin, dull its surface, and even make small scratches and marks. The same applies to jewelry and metal cleaners. Although your coin will certainly look shiny and new after using one of these products, it is likely to be worth much less. 


  • Use clean and purified water to clean coins: Tap water can contain many different minerals and chemicals which could be harmful to old coins. Wherever you’re cleaning any sort of valuable coin, it’s a great idea to use distilled water. Chlorine in tap water can discolor and devalue old coins, so make sure you use purified water that won’t cause any damage. 


How To Clean Old Coins With Soap

It is not recommended that you use this method on copper, gold, nickel, or silver coins, or really any with a high monetary value. However, if you just have some old but not-too-valuable coins to clean up, you can try using this mild solution of simple hand soap and water. You’ll need a mild detergent, a bowl of distilled water, and the dirty coin you want to clean. Follow these instructions to gently clean dirt and grime from old coins:

1. Fill a bowl with tepid distilled water, and mix in a small drop of mild hand detergent. 

2. Hold your coin by its edges and gently lower it into the solution. Swirl the coin around beneath the water to help dislodge any dirt build-up. 

3. Remove the coin and rinse it under clean water. 

4. Set the coin to air dry on a soft, clean cloth or towel. 

How To Clean Old Pennies With Ketchup 

There are all sorts of weird and wonderful tricks to use when you’re cleaning coins, including this interesting method of cleaning dirty copper pennies. Old pennies have sometimes been in circulation for decades, and they can collect an incredible layer of filth. Cleaning old pennies can be an incredibly satisfying experience; to turn heavily soiled rounds into glimmering pieces of copper. One way you can clean old dirty pennies is by using tomato ketchup, and you can find out how below. Ketchup contains plenty of salts and acids, both of which are very helpful for cleaning tarnish off copper metal. 

1. Smear a small amount of tomato ketchup on each face of the coin you want to clean. 

2. Holding the coin by its edges, use a soft-bristled toothbrush to gently scrub the coin’s surface.

3. Rinse the coin under clean distilled water. 

4. Leave the coin to dry completely on a soft and clean towel. 

How To Clean Old Silver Coins Using Baking Soda

Before you consider cleaning your coins with this method, we’d like to remind you that many old silver coins will lose some of their numismatic value after cleaning. Many coin collectors could refuse to buy silver coins that have been damaged by improper cleaning, so it’s important to be aware you might destroy valuable historical evidence. With that said, cleaning silver coins using baking soda can return a luster like you’ve never seen, which is arguably more attractive for display. If you’re certain that the risk of reducing value doesn’t matter, here’s how to clean your old silver coins with baking soda:

You will need:

  • A new packet of baking soda
  • A suitably-sized glass dish
  • Aluminum foil
  • Clean distilled water
  • Latex gloves
  • Your old and dirty coins


1. Start by opening up a fresh pack of baking soda and dipping your fingers in. You can then use your fingers with a small amount of the powder to rub your dirty silver coin. Baking soda can be surprisingly effective against tarnish buildup on silver coins, so even this small amount can be enough to clean them. 

2. If you want to remove further dirt from your coins using this method, you can add water next. Soak your coins in a glass dish, in a mild solution of water and baking soda. Afterward, rinse the coins in clean running water to remove additional residue. 

There’s a third method you could use to clean old silver coins, but it’s not one that numismatists would recommend. A chemical reaction using aluminum foil and baking soda can have your coin collection shining, but this coin cleaning technique is too harsh for rare coins. It is however highly effective at removing tarnish and stubborn dirt residue. If you’re willing to take the risk, follow these steps to clean old silver coins:

1. Line your glass container with several layers of aluminum foil. You need to ensure there are no gaps so that every part of the dish is covered. 

2. With a newly-opened packet of baking soda, cover the base of the container. You should not be able to see any tin foil peeking through the white powder, so don’t worry about pouring in too much. 

3. Lay the silver coins you wish to clean on top of this baking soda layer, with the dirtiest face pointing up. Then, pour in yet more baking soda until the old coins are covered up. 

4. Take two cups of warm water and pour them into the container over the coins and baking soda. If this isn’t enough to cover all the coins, keep adding water until everything is submerged. 

5. You can not sprinkle in extra baking soda over the areas where the coins lay. 

6. Allow this mixture to soak for a minimum of 5 minutes, so there is enough time for the chemical reaction to take place.

7. For this next step, it’s a good idea to wear latex gloves. This will protect both your hands from potential chemical damage and your coins from any impurities on your skin. Use your hands to gently rub the silver coins in the water-baking soda mixture. By ensuring the baking soda gets in every nook and cranny of your minted silver coin, you’ll remove as much dirt and tarnish as possible. When completing this step, try to be as light-handed and gentle as possible. Being too rough with your old coins could scratch them and cause irreversible damage. 

8. After you’ve rubbed away all the last bits of tarnish and grime, rinse the coins thoroughly in cold running water. 

9. Carefully dry your newly cleaned silver coins using a paper towel. If your silver coin was particularly dirty on both sides, you may want to repeat the whole process with the other face up. Make sure you allow cleaned coins to completely dry before putting them back into storage. 

This easy coin cleaning method will remove even the most stubborn tarnish and build-up of grime from silver coins, but beware of the potential cost. Although highly effective if you want your coin collection to shine, this method is not ideal if you have rare coins of great numismatic value. You should use this easy method using basic household items to clean your coins only if you’re certain the potential damage doesn’t matter. For those who enjoy coin collecting purely for the fun of it, and don’t mind about historical significance, this can be a great way to return some luster to your numismatic collection. 

How To Clean Old Coins With Vinegar

White vinegar is a substance most people have around the house which can be used to clean a whole host of different metals. It’s very effective at cleaning old coins and is popular for use with jewelry as well. All you need is a bottle of white vinegar, a large glass bowl, and the coins you wish to clean. You can use a soft toothbrush to very gently scrub at the coin too, but use caution when applying this technique. It’s always best to be on the safe side to avoid scratching valuable and rare old coins. 

1. Pour approximately one cup of white vinegar into a glass bowl, and gently set your coins in the liquid. 

2. Allow your dirty coins to soak in the vinegar for several minutes, so the acids can break down the grime. 

3. If this isn’t enough, you can use a toothbrush to help loosen dirt. Hold the coin by its edges and carefully rub your coin’s faces with a soft-bristled toothbrush. 

4. You can leave your dirty coins to soak in vinegar for several hours, or as long as is necessary. 

5. After your coins are clean, rinse them in clean distilled water and allow to fully air dry on a soft towel. 

A collection of old coins.

Using white vinegar can be a great way to clean old coins.


What To Avoid When Cleaning Coins 

We’d like to share some advice on the most important things you need to avoid when cleaning old coins, as this topic is even broader than the subject of cleaning. Because harsh chemicals and small abrasions can be hugely damaging to an ancient coin, there are many warnings and cautions about the process of cleaning. Read on to discover some of the biggest mistakes you need to watch out for when cleaning your old coin collection. 


  • If you don’t know the value of a coin, it’s best to completely avoid any process which could damage it. Cleaning your coins is a satisfying process, but there’s nothing pleasing about discovering you’ve accidentally devalued an important rare coin. 


  • Never use a standard jewelry cleaner or metal polish to clean old coins of any material. These can remove the toning which adds value to coins of certain metals, as well as leaving behind unsightly blemishes. A huge proportion of old coins offered for sale to coin dealers and numismatic specialists are rejected because they have been exposed to the wrong chemicals. These can permanently alter the appearance and the value of your coin. 


  • Avoid cleaning coins that have already started to erode or deteriorate. If the mintage details such as the date have been obscured by tarnish or other damage, it’s best to consult a professional. By attempting to solve the problem yourself, you may in fact make the situation worse. 


  • Never clean proof or uncirculated coins, no matter their age or condition. Doing so will inevitably leave tiny scratches and abrasions which will instantly devalue your coin. 


  • If you’re planning to sell an old coin, and are considering giving it a nice clean up before you do; don’t. Not only will this disappoint your buyer, but it might also ruin the chances of a sale because you have reduced the historical significance of the coin. 

How to Clean Old Coins

The best advice that anyone can offer on the subject of cleaning old coins is simply not to do it. As enjoyable and satisfying as it can be to see an old and crusty coin transform into a shining round of metal, the risks are rarely worth the result. If you are unsure of the value of an old coin or know that your collection contains rare and important items, the best course of action is to leave your coins dirty. Although this may reduce the aesthetic appeal, it’s the best way to safeguard against devaluing your precious metals investment

On the other hand, some people enjoy the hobby of coin collecting without worrying about the value of their coins. If you don’t mind about the numismatic significance of your old coin collection, there’s no reason you can’t make those rounds sparkle. Each of the methods we’ve listed for cleaning old coins can help you return luster to dirty coins, and make them more appealing to a wider audience. Use vinegar, baking soda, or just some clean running water to make your old coins look as good as new. 


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