I recently found a small reprint from a series of articles by Clyde
D. Mervis, from the old magazine Numismatic Scrapbook published by
Hewitt Numismatic Printers in the 1960s, titled “Cleaning Coins.”
Cleaning remains a taboo topic, and one of the first things that
collectors learn as they enter our hobby is that one should never
clean coins. As collectors progress on their journey, they learn that
there are some cleaning methods that can be used with caution and by
experimenting on low-value coins, but that, generally, cleaning is
something that should be left to professionals.
Mervis starts by addressing the seemingly off-limits nature of the
topic, writing that collectors can generally be placed in two groups:
“One group will emphatically state ‘Why I never clean my coins!’ ‘I
understand that you’re not supposed to do it,’ while the other group
goes along quietly cleaning their coins, but as though they were doing
something forbidden, they simply never admit it. Why?”
Connect with Coin World:
For all levels of collectors, the term used by third-party grading
services — Improper Cleaning — raises the question, what is a proper
cleaning, and at what level does a coin become improperly cleaned?
In fact, some dealers make a living working at this intersection,
making coins look more appealing to grading services, with the hopes
of getting them into nonproblem holders.
Mervis writes, “all my cleaning episodes haven’t been disastrous,
nor have they all been successful. All coins cannot be cleaned
successfully, and the experienced collector knows that.” Take corroded
coins, where Mervis notes, “Cut away the rotten parts of the apple and
get down to the solid core and you no longer have an apple. So it is
with the coin.”
Do Coin World readers clean their coins? Check our survey results!
Metal reacts with nature and its environment. The results can be
spectacular — such as a rainbow toned Morgan silver dollar — or
disastrous, as seen on many corroded bronze ancient coins.
Mervis even anticipates the issues that would follow decades later
as rare and valuable gold and silver coins would emerge from
shipwrecks. That the market accepts gold coins from the SS Central
America shipwreck and other sunken treasures attests to the advanced
technology used in restoring these coins and the market’s acceptance
of conserved coins.
Of course, the book’s closing words should ring true to coin
collectors and investors today: “It is often thought and expressed
that the chemist is a modern magician and miracle worker, but his puny
efforts sink to insignificance when pitted against Nature and Time,
while the chemist’s sole aim is to reclaim all objects.”