Cleaning copper coins at home: an overview of methods
If you decide to do numismatics, then for a presentable appearance of the future collection, it is important to know the rules for preserving its copies. Information on how to clean a copper coin yourself will also be needed by connoisseurs of antiquity who have copper relics. Not all ancient treasures abound with gold or silver jewelry; antiques are often an alloy in which copper is present. It is not difficult to restore the shine of a copper coin at home.
- What are the types of flying
- Overview of cleaning methods for old coppers
- Preparatory activities
- Mechanical cleaning methods
- How to clean a copper coin with soap
- How to use chemicals
- How to boil in soda solution
- How to apply electrolysis
- How to return the shine of Soviet trifles
- Using non-standard methods
- Helpful Hints
- Proper storage
What are the types of flying
Ancient exhibits made of copper, including coins, are considered a valuable rarity among collectors. Over time, copper becomes covered with a dark brown or black coating, forming a protective layer of noble patina on the metal. If its layers are even, then the rare copy should simply be washed from the accumulated dirt.
Hoards with old coins are often mined from the ground, where money from a very fastidious metal can suffer from corrosion. How to clean a coin, depending on the plaque covering the copper:
- the green oxide film is destroyed by thermal action or acid;
- persistent blackness, insoluble in water, is removed with ammonia or Xylitol;
- the blue coating of copper carbonate is destroyed quite quickly under the influence of acid;
- verdigris (white plaque indicates an admixture of zinc) is removed by immersion in distillate;
- red-brown nitrous stains are recommended to be cleaned with 5% ammonia or ammonium carbonate.
Attention: Coins covered with traces of oxide can harm their keeper due to the special toxicity of copper, which is constantly in contact with air. Caution is also important when working with chemicals.
To clean a copper coin at home, a numismatist will have to get a set of sterile gloves (disposable), have tweezers (wooden or plastic) on hand. You will also need a bottle of 96% ethyl alcohol and white soft paper on which the cleaned find will dry. To completely remove the remaining moisture, the ancient pennies are dipped into a container with ethyl alcohol, carefully turning the coins over with tweezers, after 10-15 minutes they are taken out.
Overview of cleaning methods for old coppers
If you are not going to give the obtained antiques for professional processing by a specialist, you can choose an effective method from the variety of home cleaning methods. In the absence of experience, you need to follow the recipes exactly so as not to overdo it and not spoil the appearance of vintage products.
Having brought home a find, the lucky owner needs to examine the found items, choosing the rarest copper coins for canning. What will need to be done:
- After a thorough inspection, proceed to clean the coins from dirt in order to understand their value. Use soft improvised materials (cloth, brush, brush), they will not damage the outer surface.
- Before you know what to clean coins from, just wash them, and boil some in an enamel container with water (distilled). Rinse under running water, dry.
- To protect the metal from oxidation processes and the damaging effects of the environment, treat the coins with alcohol and open them with an insulating coating of wax, glycerin, silicone. Now the rarity can be stored in an album with cells.
Tip: When choosing a purification method, first test it on a less valuable coin. If the copper cannot be cleaned, choose another method. When you are satisfied with the result, proceed to cleaning the remaining copies.
Mechanical cleaning methods
An effective method for a professional collector will be the mechanical cleaning of copper coins at home. Masters usually have a set of special tools at home (needles, incisors and scalpels, brushes). You will also need a drill, scraps of fabric, LED glasses with magnifying power. Using different tools, it is possible to carefully remove dirt and oxides layer by layer, avoiding damage to the noble patina.
The algorithm for carefully cleaning a copper coin in stages:
- Soaking for an hour in distilled water helps to remove dried dirt and dissolve salts.
- Impregnation with resin (synthetic) will strengthen the noble patina, protect against damage, the appearance of cavities.
- Mechanical cleaning is carried out using prepared tools and must be carried out very carefully.
To polish an old coin, you will need tools:
- Sandpaper of medium hardness. Fix its corners on the surface of the table and alternately rub on both sides with a copper circle, slightly pressing on it.
- Drill. Prepare a convenient drill, it should be wrapped with sandpaper, as well as a vise to secure the coin. Processing is performed by lightly touching the metal.
- Metal brush. It must be held with both hands, fixing the coin with a vice, pressing movements should be sharp.
The painstaking process of careful processing of each millimeter of an antique product is akin to jewelry work, it requires special patience and attention. The labor-intensive procedure does not tolerate haste and great effort, takes a lot of time and can drag on for 2 months.
How to clean a copper coin with soap
Soap treatment is considered the simplest and most common method of getting rid of blackness and oxides not only of coins, but also of other copper products. Soap foam gently removes dirt without damaging the patina, but with the only drawback — you have to keep coins in a mash for more than one month.
Step-by-step cleaning of copper coins from greenery and rust:
- Prepare a foamy solution in a glass or plastic bowl from warm water and laundry soap shavings labeled 72%.
- Place copper coins in soapy water, dipping them one at a time and distributing them evenly over the bottom so that they do not stick together.
- Leave the container for a day, tightly closing it with a lid.
If the antiques have been cleaned, they are removed from the soap mash, treated with a toothbrush. Well-washed pennies are sent to dry. Although the cleaning process with the cheapest home remedy is not the fastest, it is the safest.
How to use chemicals
If the soap failed to clean the surface of the copper coin, you will have to turn to chemistry for help. Acid-base compounds, unlike water, react with deposits on the copper surface, which allows it to be ennobled.
It is recommended to use the following tools:
- Acetic acid. Vinegar is used to remove oxides, but an aggressive agent can break the patina, reveal damage. To quickly clean a copper coin, it is immersed in a bowl of vinegar (7-20%) for a maximum of 15 minutes. Having obtained the desired result, the product is taken out and treated with a toothbrush, after which it is washed with water.
- Lemon acid. To effectively clean copper products from traces of oxidation, prepare a solution in a glass bowl from 2 parts of water and 1 part of acid. After the crystals are completely dissolved, coins are placed in an aggressive environment for a few seconds using tweezers. To neutralize the acid, dip pure copper into alkaline water.
- Ammonia solution. With the help of ammonia, strong oxides of a green tint are quickly removed. Holding the coin washed with soap with non-metallic tweezers, wipe it with a cotton swab dipped in ammonia. Then the product is again placed in a soap mash, washed with clean water and left to dry. For the procedure, you should get a respirator and gloves.
Important: The use of aggressive liquids requires extreme caution. Soaking coins in both ammonia and citric acid is not recommended. Reagents are strong, so beware of metal destruction, ammonia vapor poisoning.
How to boil in soda solution
The best way to get rid of stable rust on the copper surface of royal coins is to clean it with a thick slurry of water-based soda. It is applied to the surface of a copper rarity and brushed.
Cleaning money antiques from copper can be done in a more efficient way. Home cooking in a pot:
- Dissolve soda (5 tablespoons) in water (0.5 l). Immerse several copper products into the mixture so that the liquid covers them by 2 cm.
- Putting the pan with coins on the fire, bring the water to a boil and boil. After 30 minutes of boiling, cool the soda solution.
- Remove the cooled coppers one at a time. To remove layers of dirt, brush with a toothbrush, but without excessive zeal, without damaging the patina.
You can also clean old pennies from blackness by boiling in a small amount of oil (vegetable or vaseline), but this technology requires caution. Heated oil is able to «shoot», so the coins must be dried before boiling, and lowered into the oil with non-metallic tweezers. The result will delight with the purity of the product with the remaining beautiful patina.
How to apply electrolysis
Using electricity, not chemistry, you can clean copper money if you are familiar with school physics. Having chosen electrolysis cleaning, it is better to test the effect of the method in advance on an inexpensive coin. This will protect more valuable pieces of the collection from damage.
Scheme of phased actions:
- Prepare a small 5-12V power supply, similar to the tablet power supply. Cut off the ends of the input plugs of the device. Several wires are visible inside the rubber tube, choose 2 wires — red corresponds to plus, black corresponds to minus. Just cut off the extra wires of different colors.
- Clean the wires of red and black colors for 2 cm in length from the insulation, clamps will be attached to their ends. It is more convenient to use a ready-made crocodile clip or make 2 clips from paper clips by winding wires on them. Remember that for short circuit protection, the wires must not touch each other.
- The wires, and not the clips themselves, need to be insulated by wrapping them with electrical tape so that they do not come into contact with each other. A copper coin is attached to the clip with a red wire (plus). A black wire with a clip (minus) is fixed on a pre-selected metal object (for example, on a plug).
- Pre-prepare a glass vessel with a solution of soda — 1 tbsp. l. for 0.5 liters of water. The assembled device with a coin (red wire) and a plug (black wire) is dipped into a vessel with electrolyte (soda water) so that the liquid completely covers the entire structure.
- Now you can supply current to the home converter by turning on the device in the network. The beginning of electrolysis is judged by the formation of air bubbles around the coins. After 5 minutes, turn off the device without touching the water, remove the coins from the soda solution, after waiting 30 seconds. Rinse clean rare specimens in hot water and send to dry.
Note: If you dissolve ordinary salt and flour in equal proportions in the same amount of vinegar essence, you can restore shine to copper products. Tarnished coins will also shine if rubbed with a wad of old black and white newspaper.
How to return the shine of Soviet trifles
Among the collection coins, many numismatists have a separate niche for rubles and multi-colored trifles of the Soviet period. Over time, the external attractiveness of the money of the past changes, then the copies depreciate.
However, cleaning copper-nickel coins of the USSR is not particularly difficult. It is enough to treat each item with tooth powder or toothpaste applied to the toothbrush, followed by thorough washing.
Using non-standard methods
Coins, as well as other exhibits containing copper, can be effectively cleaned of layers of rust and dirt with ordinary food. The secret of the method is in the presence of an acid that dissolves accumulations of copper oxides.
Here are a few of them:
- By practicing gentle cleaning with kefir, you will not damage the patina. Slightly contaminated coppers are poured with a fermented milk product for only an hour, but kefir must be fresh.
- Do a similar manipulation with ketchup, but it takes only a few minutes to withstand vintage products. Remove the rest of the ketchup from the coin with a cloth flap, wash with soap.
- If there is a lemon in the refrigerator, cut it into 2 parts, do not put a copper coin in each or just stick it in the lemon. After 15 minutes, wash off the fruit’s acid using a toothbrush.
- Drink «Coca-Cola» not only quench your thirst. It is enough to immerse ancient copper products in a universal detergent for only 2 days, cleaning can be accelerated by heating a fizzy drink.
- If you have time, use the Trilon-B chemical reagent. In a ready-made product that does not damage the metal, immerse a copper coin for 15 minutes to rid it of rust thickness. Several procedures may be needed.
Of all the options for household chemicals in the fight against rust and to protect against its appearance, Cilit cleaner, enriched with phosphoric acid, is the best choice. The agent is poured into a plastic container, the coppers are kept in a chemical solution for 15 minutes, then wiped with a cloth and washed. In addition, the preliminary cleaning of coins from any kind of metal is performed by ultrasound, having prepared an ultrasonic bath instead of a brush with soap.
If it is important for a treasure hunter to carefully remove a find from the ground, then in order to preserve its presentation, you should know how to clean an old copper coin by choosing the right method.
How not to clean copper
A numismatist without experience should not choose abrasive powders and patina-damaging tools. Household chemicals, as well as concentrated acids, can ruin the pattern of old coinage. It is dangerous to use ferric chloride — saline solution for etching circuit boards will corrode a copper coin, and under the influence of high temperatures your find will simply crumble.
How to dry a collection
Drying of copper coins after cleaning work must be mandatory, otherwise copper coins will lose their attractiveness due to oxidation. During the drying process, paper towels are used to soak moisture, and a rag is prepared for wiping, leaving no traces. You can use a drying cabinet, but you will have to monitor the temperature (no more than 100 ° C).
Note: If you managed to clean the coins too thoroughly, then they may not look aesthetically pleasing. To refine copper, experienced collectors are engaged in the imposition of artificial patina.
The ennobling mixture is prepared according to the following recipe:
- Copper sulfate (25 g) and potassium permanganate (2.5 g) are dissolved in water (0.5 l).
- Coins are dipped into a solution heated to 90 ° C, constantly turning over.
- Having obtained the desired result, the products are dried, covered with a protective layer.
Unlike a noble patina, harmful oxide is difficult to remove. But after cleaning, it is recommended to cover copper coins with a protective layer of petroleum jelly or glycerin, or use ready-made branded products.
However, it is not always possible to clean ancient coins quickly. Their appearance may suffer not only due to a long stay in the ground, metal specimens oxidize from storage in the room. How numismatists store collections:
- in special albums with pockets;
- in cardboard tablets with round slots;
- in glass cases that improve visibility.
Experienced collectors advise once a year to check the condition of preserved copper pennies, but avoid touching them often. If necessary, take the coin by the edge, then rinse it and dry it. If you follow the storage rules, valuable specimens will not need frequent cleaning, and a copper rarity will delight you with brilliance for more than one year.