The vinegar and salt mixture dissolves the outer layer of dirt. Flip the pennies over and wait another 30 seconds. Then remove them, rinse them with water, and dry. Now you have two clean, shiny pennies!
Acid based cleaners will eat away at a coin's surface diminishing its value. According to research professor Vinod Patel, washing coins with natural white vinegar and iodized salt in distilled water is a non destructive way of cleaning coins.
Add a small amount of water to a tablespoon of baking soda to form a paste. Apply the paste to each coin using an old toothbrush and scrub gently. Rinse the coins to reveal the now-shiny surfaces.
The combination of vinegar (a weak solution of acetic acid), and table salt (sodium chloride) helps to dissolve the copper oxide, and also forms the blue copper(II) ion, which is soluble in water. The penny becomes shiny again!
Never use metal polish or acid dip to clean your coins! Using these chemicals will cause abrasions or chemical reactions with the metal, permanently damaging your coin. This damage can never be fixed or undone. Additionally, these chemicals can be caustic and cause injury or even death.
Most Cleaning is Destructive: It Can Literally Change the Surface of a Coin. Any cleaning that requires rubbing leaves microscopic scratches. They are not apparent to the naked eye, but a collector will see them. A collector will look for them.
To clean your coins without risking damage to the surface and a reduction of value, you should use only water. Grasp a coin by the edges, and hold it under a gentle stream of lukewarm distilled water. Flip the coin over so that the reverse side is also wet. Then, gently pat the coin dry with a soft cotton towel.
Vinegar. A common ingredient in DIY eco-friendly cleaners, the acetic acid in white vinegar can help wear away the contamination on your coins. Soak your coins in a glass or other non-corrosive container for at least 30 minutes, up to overnight, and then wipe with a clean cloth or scrub gently with an old toothbrush.
Within about 30 seconds, the pennies in this bowl will start to shine. The vinegar and salt mixture dissolves the outer layer of dirt. Flip the pennies over and wait another 30 seconds. Then remove them, rinse them with water, and dry.
With a little time, minimal effort and some basic household supplies, such as vinegar and baking soda, you can bring out the shine in even the dingiest of tarnished pennies. Cleaning coins with baking soda and white vinegar is effective and easy to do.
Coins that are obviously dirty can be run under water (with a very mild detergent) and left to air dry. A short soak in olive oil may remove unwanted gunge. For cleaning corroded coins the damage is already done, they will forever show pitting into the coin surface. This is as far as anyone should go with cleaning.
Washing your coins with olive oil is the safest way to clean your coins as you cannot leave the coins in olive oil for too long. It has been used for years and is very reliable. Put olive oil in a closed container, and then place your coins in the container. Change the oil once or twice a month.
The oil-base makes WD-40 reasonably effective at removing it without a lot of work. There is of course some sacrifice when this stuff is removed but fortunately the metal underneath is in pretty good condition and the coin, in hand, is much more presentable.
Coke and off-brand colas will quickly remove the tarnish. Just don't drink the coke afterward. Coke contains phosphoric acid that cleans the oxides. Try a variety of citrus juices to see which works best or simply let your pennies soak in lemon juice.
Boil 1 1-/4 cups of water, add 2 teaspoons cream of tarter, 2 tablespoons vinegar, and 2 tablespoons salt. Add coins and boil for about 3 minutes or until tarnish is removed. Remove coins from water and dry with a soft cloth.
Make sure your coins have been cleared of all dirt, debris and other objects prior to visiting the kiosk to ensure a successful transaction. Items like food, screws, dirty or sticky coins and other objects will jam the machine.
This is because anything that touches a coin has the potential to damage it at the microscopic level. The more abrasive a cleaner is used to clean the coin, the more likely it is to remove the upper surface of the coin - damage that can never be undone.
Don't clean your coins! Not only does this cut their value by as much as half (or possibly even more), but it will be an immediate deal-breaker for many dealers who would've otherwise wanted to buy your coins if only they were left in their original condition.
Polishing and/or cleaning coins can reduce their value. Older coins that show deep age coloration are more desirable than coins whose surfaces have been stripped away by improper polishing or cleaning. If you do polish a coin to remove dirt, use mild soap and water.
Vinegar and Salt
Mix vinegar with salt. Place pennies in the solution and let them sit for a while, and then use a clean, soft toothbrush to clean any dirty areas. Rinse the coins, and then polish them with baking soda paste.