by Skip Fazzari
Fingerprints are like a cancer
to a coin, and can become irreparable if they
are ignored for too long. Skip Fazzari describes
the different types of fingerprints and what you
can do to correct them.
For most of you, habit and experience have
lessened the odds of marring the surface of your
coins with fingerprints. You hold a coin
properly — by its edges and close to a soft
surface. Occasionally, there might be a lapse in
this protocol but in most cases, we can assume
that any fingerprints found on your coins
resulted from carelessness or mishandling by
It is difficult to know how long a fingerprint
has been on a coin. Sometimes, especially in the
case of Proof coins, they are easy to see the
moment they occur; however, in most cases,
fingerprints are not detected when they are
fresh. Fingerprints are like a cancer to a coin.
If ignored for too long, the chemicals in our
body oils will actually etch the coinage metal.
Over a period of time, and depending on their
chemical makeup and the environment, they will
“set” on a coin’s surface, making them difficult
to remove. Copper and silver coins are the most
likely to be permanently damaged in this way.
Once this happens, the traces of fingerprints
are virtually impossible to remove without
abrasive cleaning that ruins more of the coin’s
original surface. For the most part, gold is not
susceptible to any type of permanent damage from
fingerprints; however, on a few occasions, I
have encountered a print pattern on gold that
cannot be removed.
A “fresh” fingerprint is one that can be removed
easily. A solution of soap and water will often
restore the coin’s surface. Between the extremes
of fresh prints and those that are etched into
the surface are blemishes that may be removed
with a mild acidic coin dip. The key to any form
of treatment is to keep the coin’s surface as
original as possible and free from any of the
hairlines we associate with improper cleaning.
As with all conservation efforts, these
techniques are best performed by experienced and
Two other types of “fingerprinting” come to
mind. Occasionally, a “reverse print” can be
seen on a coin. This occurs when grease
deposited on the coin from our skin protects its
surface from further contamination. The print
only becomes apparent as the surrounding surface
is toned. The other type of print occurs when
the hazy patina or “skin” of a gold coin is
marred by the shine of a greasy smudge or print
due to mishandling.
Fingerprints that have become “set” can have a
much larger effect on a coin’s grade than one
might think. This is because they are very
noticeable when they are fully developed and
they detract so much from a coin’s eye appeal.
Their size, color, and location combine to
determine how much they will influence a grader.
In many instances, the attempt to remove a
fingerprint will make matters worse. Mature
prints often appear as brown stains on red
uncirculated copper and tan to dark brown stains
on brown copper. If these coins are “dipped” in
an effort to remove the fingerprint, the copper
will turn pink and the coins will likely be
rejected by the major grading services because
of their artificial color. Therefore, this
procedure is not recommended for copper coins.
Fingerprints on silver coins usually range from
gray to black. A darker stain usually indicates
a deeper reaction. Dark prints on silver coins
will turn gray when the coin is dipped.