Cleaning Tips

Cleaning Tips

 Cleaning your Uncleaned Roman Coins


Have a tip for cleaning not included here?  I want this to be the most

comprehensive cleaning section on the web! 

Email it to me and I’ll put it in.

Cleaning  your coins can be fun and exciting, and can also be about the most

frustrating thing on the planet!  These instructions will help you along the way. 

I’m starting with all of the techniques that I know and together we will build the

best list of cleaning techniques available on the web!   There is no one ‘right’

method for cleaning coins. What works for one coin may be an absolute disaster

for another. The best solution seems to be a combination of methods and

experience. Experiment to find the combinations that work right for you.

The best tool is patience.


Many of the ancient coins have a patina, which is a colored layer (usually green,

red, brown, or black) that builds up on the coin over the centuries, you want to

remove the dirt from the coin and not the patina.  That is the correct way to do

it.  If you use a technique that removes the patina, you decrease the coin’s

value and you risk damaging the coin.  Your objective when cleaning coins should

be just to remove any dirt and incrustation that obscures the coins design and

not to return them to the way they looked when they were first minted. Don’t

clean them down to the bare metal. Ancient silver coins can also have a form

of patina on them, but we call that Toning. Toning can range from a very light to

a very dark grey. A properly toned silver coin can be very pleasing to look at,

 as opposed to the bright silver coins that are so common today. So please,

 if you have a toned silver coin let it be.

Many of the techniques here will remove the patina.  I will try to indicate when

that is the case.

Tools of the Trade 

The most common tools and ingredients are:

Olive Oil


Soaking Dish


Metal Pick

Brass Brush

Baking Soda


Magnifying or Jewelers Glass

Commence Cleaning

There is some consensus on what the normal way to clean a coin is:

A good first step is to wash the coin with water and dish soap. This will get

the surface dirt off.  Then scrub with the toothbrush, maybe applying a little

baking soda to the coin as you scrub.  Soak it in Olive Oil overnight, and

then repeat.  And repeat…and repeat…and, well you get the picture. 

This process can take days, weeks, or even months. Use the toothpick

to get dirt out between the letters. I find that valve oil, instead of olive

oil will work a little faster.  Valve Oil will not darken the patina like olive

oil will either.It is only good if you are leaving the patina in tact, as valve

oil on the bare metal can leave some pretty funky colors. You can find

valve oil in any musical instrument shop.This is the only way of cleaning

the coins that I know of that leaves the patinas in tact for sure.  The most

important ingredient is PATIENCE!

Slow and Steady may win the Race, but I want to see my coins!!!

Now for all of us who are doing this for fun, here are some of the ways to

clean them up a little faster and have the result be a beautiful

coin that you can attribute and display.

A metal pick can be a life-saver.  Careful not to scratch the metal.

A dental pick works great, but even a push pin makes for a good scraper and


A Shocking Development

There is also a fast way of cleaning coins.  Through electrolysis you can

quickly remove the dirt from a coin and have a nice looking coin within a

day or two.  To build an electrolysis machine you will need an AC adapter,

a stainless steel spoon, salt or baking soda, a bowl, and alligator clips.  

Cut the end off the cord of the AC adapter.  Separate the wires.  Strip some

of the shielding away from the wires and wrap the wires, each around

the end of an alligator clip.  Then fill a plastic or glass bowl with water and

put in about ¼ cup of salt or baking soda (baking soda is more gentle). 

Stir, then attach one of the alligator clips to the spoon, and put the spoon

in the water.  The alligator clip attached to the spoon should not be in the

water.  Bending the spoon helps.  (Careful as bending and using spoons

and bowls can cause adverse reactions from spouse).  Then put the

other alligator clip in the water.  Plug it in and observe which one fizzes. 

Then unplug it.  If the spoon fizzed, then detach the alligator clip and put

the other one on the spoon.  The fizzing end should attach to the coin. 

Then attach the coin and put them in the water.  Plug it in again, and

watch the dirt fly off.  Before long a layer of dirt and metal will form on

the surface of the water.  You will need to change the water whenever this

gets thick as it can be corrosive.  I find that 20 minutes works for me, but

that may vary with the coin, the amount of water and the amount of salt. 

 More salt means it works faster.  BE CAREFUL!!  I’ll try to have pics before long.

You can get a nasty shock if you aren’t careful.  Don’t go touching the water

or the spoon, without unplugging it.  After each 20 minute treatment take

it out and scrub it with a toothbrush and rub it on the towel.  I find that

dabs of the valve oil works well for this part.  Then just repeat until you

have a nice coin.  Now this usually destroys the patina which greatly reduces

its resale value, and also removes a small layer of metal, which, if there

wasn’t much on the coin before, there certainly won’t be now, but it leaves

you with a beautiful coin when done properly.

Tips from customers:

For what it’s worth, I bought the cleaner at JC Penney for $18.99. I know

it’s a terrible thing to do, but I’m going to dip the coins in CLR tomorrow

to strip away much of the patina. My daughter has show-and-tell Monday

and wanted to take “shiny” coins.
John – Mesa, AZ

Instead of a toothbrush, I found that a bristle brush from a .22 cal rifle

cleaning kit did a great job of removing some of the more stubborn dirt.

Not the brass tip, mind you, but the black bristle tip. Should be able to

 find them in any sporting goods store.
Bill – New Jersey

I have had very good luck with using Calgon water softener that I bought

at the supermarket (in the laundry detergent section). After every soak

in olive oil, I clean off the oil with warm distilled water and a little soap.

Then I add one tablespoon of Calgon to a cup of distilled water, mix it in

a small tuperware style container and shake for 10 seconds. Immediately,

layers of dirt fall off and soften it so it can be more readily picked off.


Toothpicks are a little fragile and too small to get leverage. If you get the

right type wooden chop sticks and sharpen it (not all woodchop sticks

easily sharpen to a fine point, so try several brands) with an electric pencil

sharpener, you get a nice tool to use and it can be resharpened.


TOILET BOWL CLEANER!  Lol. then a soaking in calgon and Joy detergent,

then a good cleaning with a brass brush. they come out beautiful  Only

leave them in the the cleaner for 10-15 minutes.

Lolly2 –


It appears that this method strips the patina.

 However, if you are in it for the fun…so what.


I have a cleaning tip for you, It works great the best so far when

it comes to soaking compounds:

The carpet cleaning fluid that comes with “The Rug Doctor” carpet

 cleaning machine you can rent from Supermarkets. Just soak the coins

full strength for 1 day at a time…You will be amazed!!!



This one looks like it leaves the patina intact.


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