Think Twice Before Cleaning Any of Your Coins

By Dr. R. S. Bart Bartanowicz, Coins Magazine March 03, 2010

Forrest Gump’s words rang in his head, “Stupid is as stupid does.” Our numismatist’s 1945 “micro S” Mercury dime had come back from the grading service as “cleaned.” The dime’s value had been greatly diminished by his less than artful cleaning.He remembered the day of his fateful mistake. The sun was shining, birds were singing and flowers were in bloom. Amid all this loveliness, he was sorting his coins.

He had quite a few Mercury dimes in two-by-two holders. Looking through them, the 1945 “micro S” dime literally leaped out at him.

He had forgotten about this purchase of many years ago. It was a gem coin that he had meant to send off to the grading service. Examining the dime, he was impressed by the luster and wonderful strike.

The only thing wrong was some dark “rim toning” from 3 to 6 o’clock. The toning was a genuine distraction to the rest of the coin.

Examining the coin through his loupe, he saw that the coin had never been cleaned as was evidenced by the luster and lack of hairlines. The dark bluish hue of the rim toning just did not sit well. Without the toning the coin would be stunning.

What to do was his quandary.

The toning would not impact the coin’s high grade, but it would have so much more eye appeal if it were totally white. In his head he heard voices saying “Clean the coin. Clean the coin.”

Cleaning any coin went against the advice he always dispensed to newcomers, which was:

“Don’t clean coins unless you’re willing to suffer the consequences from a botched cleaning.”

It was only a little toning and a quick little swish of a commercial coin cleaner would eliminate it. What could go wrong? To be safe he would experiment with a coin or two from his pocket change to make sure he had his technique down so as not to mar the luster or leave any hairlines.

He had cleaned coins in the past with a simple washing, such as his coffee can purchases of coins deposited in can and jars over the years. He seldom used commercial coin cleaning solutions unless the coins had been badly contaminated with dirt, grease, PVC slime/residue and other foreign matter.

These solutions had been used with inexpensive coins. He considered this to be conservation vs. letting the coins deteriorate due to surface contamination.

He used a cotton ball to apply the cleaner in a gentle blotting motion so as not to create swirl marks or hairlines. Still the toning seemed resistant and stubborn.

As he prepared to blot again he heard the voices: “A little more pressure and rub it just a tiny bit to remove it all.” Now other voices called out to him: “Don’t do it. Don’t do it.”

Snapping back to the present, our numismatist murmured, “just a little rub,” as he applied the cotton. He followed the cleaning with a quick rinse of the coin in water. The toning had disappeared and the coin look wonderful, but perhaps with a sense of foreboding he did not examine the coin under magnification.

Now, weeks later, he had the dreaded results. “Stupid is as stupid does.” He would, of course, be quiet about his failure. Had the coin come back without mention of the cleaning and in the grade he wanted he would have proclaimed himself to be a genius.

The moral to our story is that sometimes things are best left alone. With cleaning coins you need to know what you’re doing.

There are several things along the way one needs to consider before cleaning any coin. The first one is: Why do you want to clean the coin? If it’s because of toning, remember toning is a natural condition that should not affect the grade unless it is covering marks, blemishes etc. Secondly, can you stand looking at a botched job? For instance, a “pink coin” is not attractive. This has been known to happen with copper and bronze pieces.

Thirdly, can you afford to lose the value of your coin if it is damaged in the cleaning? Additionally, get all the advice you can. Discuss the cleaning with a dealer or fellow collector.

There are books that discuss the cleaning of coins and all the pitfalls. Getting educated will help.

Finally, if you have a coin that you are tempted to clean, consider selling or trading in the coin to someone who may appreciate it. There are collectors who actively seek attractively toned coins. This is the preferable route to ruining a coin’s numismatic value.

If after all this you are still intent on cleaning your coin do be careful. Try your cleaning technique on some coins from your pocket change.

Looking over the demographics of the hobby most of us are not chemistry majors. Cleaning, or better said conservation is best left to the professionals.