cleaning coins...what should i use?

koreansteve · December 17, 2003 11:53AM

No, i'm not going to be cleaning or "artificially purifying" any old, valuable coins. What i wanted to do was try various cleaning methods (dipping, scrubbing, and others that i don't know) on today's currency so that i can get a feel for what a cleaned coin looks like.

So, if you guys wouldn't mind listing some/all of the various cleaning methods (it'd be helpful if you were fairly specific and told me exactly what chemicals are used) i'd appreciate it. I'm looking to clean some washington quarters, FDR dimes, jefferson nickles, and especially some lincoln pennies (i'm currently collecting IHC and pennies are the closest thing to them).

Oh, by the way, i'm looking for non-lethal cleaning methods...so no cyanide based cleaning substances. thanks.

Compa · December 17, 2003 12:01PM

No personal experiance yet ... but lots of info here: COIN CLEANING SECRETS OF THE ANCIENTS

JrGMan2004 · December 17, 2003 12:05PM

Try using... I think it's Olive Oil on the pennys... they usually make em REAL shiny

CaptainRon · December 17, 2003 12:10PM

Try doing a search here on the forum with a couple differant keywords like cleaning or dipping. You may have to poke through quite a few threads, however there are many that discuss differant methods.

LincolnCentMan · December 17, 2003 12:17PM

Olive oil on strong XF/AU cents that have no origional mint luster.

I wouldnt have a clue on anything else.

David

Newmismatist · December 17, 2003 12:31PM

Here's some info that i posted to a previous thread:

That said, here's the what every newbie should keep in mind when he (or she) has the urge to dip (clean coins):

1. Water is the universal solvent - so add a little mild liquid soap to warm water, rinse what ever it is you want to clean - it will probably remove light oils, greases, and surface dirt or dust - It will NOT in any way affect toning. If after a mild soap & water rinse the coin looks better (dirt's gone) STOP - moving up the ladder (stronger cleaners may do more harm than good). Important - RINSE well, In fact if you miss this point, I'll repeat it RINSE well - dry carefull (pat don't rub - SOFT cotton towel - actually those really soft cotton baby diapers work very well.

2. Try alcohol - Alcohol is the other solvent that will clean & remove surface dirt and shouldn't harm the coin - after rinsing with alcohol, you may not even have to pat the coin dry as it evaporates quickly - won't change the toning and will remove any surface contaminates that are soluble in alcohol.

3. Acetone - very volitile - will remove PVC and other surface contaminents - be very careful with copper- As it evaporates, it may slightly alter the toning - will not affect the toning on gold or silver UNLESS the toning is an applied AT tone that is soluble in acetone - if that happens check with the doctor from whom you purchased that "original" toned coin. (WORK IN A WELL VENTILATED AREA - DEATH is a side effect if you breath too much of this stuff)

4. There's another product, called "Trik" or dissolve (Tri-chloro-floro-ethane?) - it will remove greases & PVC, I think this stuff has been banned - (WORK IN A WELL VENTILATED AREA - DEATH is a side effect if you breath too much of this stuff) - Does not affect toning (unless the AT variety).

5. Patroleum based solvents: Example - paint thinner, or gasoline - They will remove substances (oils & greases) that are soluble in - well - patroleum based solvents - if for example a coin has been "coated" with a clear protective layer of whatever? (Old time collectors used to shellac or lacquer they surfaces of their coins to prevent them from toning or spotting) - so occsionally you'll find coins that are "coated" with sometype of "protective" layer that you may want to remove. (WORK IN A WELL VENTILATED AREA - DEATH is a side effect if you breath too much of this stuff, also needless to say very flamable)

6. Lacquer Thinner - will remove lacquer, nail polish etc - don't have my college chem book, but I think this is also a Patroleum based solvent. (WORK IN A WELL VENTILATED AREA - DEATH is a side effect if you breath too much of this stuff, also needless to say very flamable).

Now in theory none of the above will affect real natural toning - but if whatever coin you're dipping has had the "toning" added by an intrepid doctor - the AT may "disappear" or even change color from solvents 2-6 - so if the coin may be AT, you might not want to mess with it, unless you really know what you're doing.

Dips that remove toning:

1. Virtually all acids will remove the toning on a coin - the acid "bonds" or reacts with the oxygen/sulfer atoms on the coin, and strips them off leaving bare metal - On heavily toned coins, contrary to what anyone has said, the coin will probably be severely impaired after an acid dip, because the heavy oxygen/sulfer atoms have formed a thick chemical layer on the coin, and removing them removes the luster - WHICH CAN NEVER BE RESTORED - the barbar half shown above is probably a good example of a heavily toned coin that was dipped - afterwards they all have a hazy look that you think will come off with another quick dip, but it will not, it'll only get worse. These coins tend to re-tone a fugly yellow brown color & look even worse - Failure to properly rinse will result in acid residue which will cause ugly ugly black spots on silver and will ultimately ruin the coin.

2. Strong bases - these may also remove toning or chemically react with the existing toning and change the look of the toning - not generally used or sold to clean coins, but I think MS 70 is a base that is stronger than ordinary soap - and I think it chemically reacts with some types of toning - I don't think it actually removes the toning as much as chemically reacts with it - IF there's a chemist here on the forum, maybe he or she can explain what happens when a strong base is used on copper, nickel or silver.

THe bottom line with dipping or cleaning coins is this:

IF you HAVE to do it, experiment with bullion type coins, or coins that have little value over face - Of the 1st 100 coins you dip, you'll probably make 60-80% worse not better (if you're really good you can ruin 100% of the coins you dip!) - remember what they look like immediately After you dip it, is not necessarily what it will look like a week or a month later - Just think of the slabbed coins that you've seen that look fugly and you swear that the PC or NG graders were blind when they graded that fugly coin - chances are it did NOT look like that when they graded it - removing the protective "toning" layer from a silver or copper coin leaves a coin that is highly reactive to atmospheric oxides, sulfides etc and unless the coin is completed "sealed" from any contact with atmospheric pollutants, IT WILL react with those substances and it may turn very UGLY -

Now all of the above said - there's probably 10% of coins that can be "improved" by dipping - knowing which 10% is the trick - with the other 90%, you're gonna have a lot of downside -

Have fun!

islemangu · December 17, 2003 1:34PM

Make sure to rinse good

techeff · December 17, 2003 2:13PM

Use a lot of sense... And if you have any concern send the coin(s) to NCS. They do a pretty nice job.

cleaning coins...what should i use?

Comments

Leave a Comment