Andrew Brunhart has worked for the WSSC, the US Mint, as well as the Bureau of Engraving and Printing. Visit http://andrewbrunhart.net for more information.

2. There are plenty of highly valuable US error
coins and die varieties floating around today.
While most people don’t notice them
because their distinguishing characteristics
are so small, this slideshow will help you
identify whether or not you’re holding a
fortune in the palm of your hand.

3. 1969-S Lincoln Cent
With a Doubled Die
Obverse
This coin is exceedingly rare. The
early specimens were confiscated
by the Secret Service until the U.S.
Mint admitted they were genuine.
Counterfeits abound, but usually
have the wrong mint mark. To
identify, look for clear doubling of
the entire obverse ("heads" side)
except for the mint mark. If the
mint mark is doubled, it is probably
a case of strike doubling, rather
than a doubled die, which isn't
worth much. Approximate value is
around $35,000 or more in EF-40 or
so.

4. 1970-S Small Date
Lincoln Cent With a
Doubled Die Obverse
As with virtually all true doubled
die varieties, only one side of the
coin shows doubling. If both
sides exhibit doubling, the coin
probably exhibits strike doubling
instead, and is worth little. To
detect, look closely for doubling
in LIB of LIBERTY and IN GOD WE
TRUST. Approximate value is
around $3,000 in EF-40 or so.

5. 1972 Lincoln Cent
With a Doubled Die
Obverse
The 1972 (no mint mark) Lincoln
Cent doubled die variety shows
strong doubling on all elements.
Use a "die marker" to help verify
your finds. A die marker is a
gouge or crack that identifies a
particular die. Look for clear
doubling of all obverse elements;
look for a tiny gouge near the
edge above the D in UNITED as a
die marker. The approximate
value is about $500 in EF-40 or so.

6. 2004-D Wisconsin
State Quarter With
an Extra Leaf
There is some defect on the die
that makes it appear as if there's
an extra leaf on the lower left-
hand side of the ear of corn on
the reverse. There are two
varieties: the High Leaf and the
Low Leaf type. Approximate
value is $200-$300 in MS-60 or so.

7. 1999 Wide "AM"
Reverse Lincoln Cent
This variety is known for 3 dates,
1998, 1999, and 2000, with 1999
being by far the rarest. The mint
erroneously used a proof die to
strike normal circulation coins. The
AM in AMERICA on the reverse is
clearly separated in the Wide
variety. In the normal variety for
these dates, the letters AM are very
close or touching. Approximate
value is $5 to $25 in circulated
condition, $75 to $600 in MS-63 or
better depending on color. 1999
brings the highest prices, with 2000
being second.

8. 1982 No Mint Mark
Roosevelt Dime
At the point in time that these
coins were made, the dies sent to
the individual branch mints would
be punched with the proper mint
mark letter for that branch. This
variety is believed to be caused
because one or more non-punched
dies were used to make coins. (The
letter P was being used for
Philadelphia on dimes at this time.)
If your 1982 dime is missing a mint
mark, it could be valued at $30 to
$50 in AU-50, more for higher
grades.

9. Presidential Dollar
Edge Lettering
Errors
Ever since the first Presidential
Dollar (the Washington Dollar
issued in 2007) there have been
errors associated with the lettering
on the edge of these coins. In some
cases it is missing entirely. In
others, the edge lettering has been
placed there multiple times. To
detect, look at the edge. The
inscription should appear fully
incused all around the
circumference of the coin. Missing
or doubled inscriptions are rare and
valuable, anywhere from $50 to
$3,000, depending on the
President.

10. 1995 Doubled Die
Obverse Lincoln Cent
This doubled die variety
generated a lot of mainstream
interest when it was featured as
a cover story in USA Today.
Specimens are still being found in
circulation all the time. There is
clear doubling in LIBERTY and IN
GOD WE TRUST. Approximate
value is $20 to $50 in Uncirculated
condition.