How to Clean Your Coins with Electrolysis

When That Soft-Bristled Toothbrush Just Won’t Do the Trick

I thought I’d take a few moments today to write a post on how to clean your coins with electrolysis. Before I start, I would like to put forward a disclaimer that I do not recommend performing electrolysis unless you fully understand what you are doing.

Initial Disclaimer

I would also not recommend electrolysis on items of questionable value or those items that you cannot identify at first glance – you never want to jeopardize the value of your find by attempting to clean it in any capacity.

What is Electrolysis?

Disclaimers out of the way, electrolysis is quite simple and can be performed at home at little to no cost. It’s a scientific process that shoots electricity through your metal object to remove the dirt, rust and corrosion that has accumulated over the years from being buried in the ground.

What You’ll Need

Here are a few items that you’ll need to get started:

  • 1 plastic or glass container – do NOT use metal.
  • 12V power adapter – you probably have an old power adapter lying around the house (I used one from an old wireless modem).
  • 2 alligator clips that you can pick up from any hardware store for less than $1.
  • 1 piece of wire (with both positive and negative).
  • 1 old spoon. If you don’t have one, go to the local thrift store and buy one for $.05.

Once you’ve gathered these items, it’s time to put on your Macgyver hat and get your hands dirty!

Here’s what you need to do:

  • Step 1: Cut the small end off your power adapter (the part that would go into whatever electronic device you used to use it for).
  • Step 2: Pull apart the positive and negative wires about half way to the DC plug then strip off about ½ inch of the plastic wire covering from the ends, exposing the metal wiring.
  • Step 3: Attach the alligator clips to both wires (detailed instructions here:
  • Step 4: Connect the negative alligator clip to your coin/object then connect the positive clip to your spoon.
  • Step 5: Fill your plastic/glass tube with warm water, adding about 2 tablespoons of salt and a few drops of lemon juice.
  • Step 6: Submerge both the spoon and coin/object into the water with enough space between each other so they never touch (the 2 ends must NEVER touch each other).
  • Step 7: Put on a pair of rubber shoes, double check the spoon and coin are nowhere near each other, and then plug your DC adapter into the wall.

Here’s what your little science experiment should look like once you’ve set up everything:


After you turn on the power, you should see small bubbles start to form around your coin/object (see image below). If you notice them coming from the spoon instead, you’ve got to start over and reverse your wires.

I recommend that you keep a close eye on the process and not leave the room for more than 5 minutes at a time. When first starting out, you should stop the process and evaluate your coin/object every 5 minutes to see if it’s been zapped enough.

Additional warnings:

  • Make sure you feel the back of the DC adpater every so often to make sure it’s not getting too hot (you don’t want to start a fire from cleaning a penny).
  • Keep kids out of sight when performing this method. Also warn any other adults in the house not to go near your setup while the juice is on.
  • When in doubt, don’t try to clean your find. The value of your find can disappear if you try to clean.

The only time I really use electrolysis is when I know the value of my find is low or I have no intention of ever putting it up for sale.

My Case Study

Last weekend I dug 3 wheat pennies at a local school yard with my E-trac. 2 of the pennies I could clearly make out the dates – however the 3rd barely even passed as a penny.

So I decided that 3rd wheat penny would be a perfect candidate for electrolysis. After about an hour-long bath in a pool of electricity, my wheatie came out quite nice (that is to say I could actually tell it was a wheat penny and not a circle of solid rust).

The Results

Here are my before and after shots to show you how effective electrolysis can be (note that the before shots were taken AFTER attempting to clean the coin with a toothbrush and warm water).

Before & after shots of the obverse & reverse

Final disclaimer: We do not advocate attempting the electrolysis process and will not be held liable for any ensuing injuries and/or damages. Extreme caution should be taking when dealing with electricity. The gasses emitted from this process can also be highly flammable. When in doubt, seek out a professional.

In other words, DO NOT TRY THIS AT HOME!