What The Numbers Mean: Learn how to use those confusing numbers often seen in identifying errors and die varieties.
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By J. T. Stanton, N.L.G.
In the study of mint errors and varieties, identification numbers appear
more abundant than with the regular segment of the hobby. These can seem to
be very complicated and confusing. The numbers are simply easy methods of
precisely identifying various varieties. By using these numbers, other
specialist can quickly and easily determine exactly which variety is being
mentioned. Other numbers are used to describe rarity, and even a certain
class or type of variety. But the important fact is that with the use of the
numbers, most people can mention a certain identification number, and most
dealers and collectors will know right away exactly which variety is being
mentioned. At the very least, a dealer or collector can look in various
reference sources and find that corresponding number along with a photo or
photos, which helps them in their quests for knowledge.
Most of these identification systems are simply numbers listed after the
date and denomination. Some are more complex identification listings and
include letters or symbols to further identify the variety or error.
Additionally, some of the identification listings can be confusing, as a
couple may use the same prefix. In this case, one must be able to assume
which identifier the writer is mentioning. But this can usually be done
The Sheldon Scale C For many years, the only method of reasonably
identifying rarity was with the use of Sheldon Scale. This scale was
designed at the time to identify rarity of Large Cent varieties. In this
case, the Sheldon Scale worked very well, as mintage figures were relatively
low. No question. The Sheldon Scale was further adopted for use with many
other series and denominations, as it was the only common scale in
existence. However, it was not quite appropriate for most series, most
varieties, or even most errors.
The Sheldon Scale was simply a progression of eight levels, in which the
population of all Large Cent varieties were to fall, and was prefaced with
the letter "R", indicating Ararity.@
The Sheldon Scale
R‑2 Not So Common
R‑4 Very Scarce (population est. at 76‑200)
R‑5 Rare (31‑75)
R‑6 Very Rare (13‑30)
R‑7 Extremely rare (4‑12)
R‑8 Unique or Nearly So (1, 2 or 3)
As we indicated previously, other writers adopted this scale to represent
coins that were considered scarce or rare, however, as you can imagine, the
scale would not be appropriate for many coins. For instance, if using this
scale, the 1955 doubled die Lincoln Cent would be considered common or not
so common. Yet in today=s market, the coin is in fact scarce or rare. It all
has to do with what is relative.
The Universal Rarity Scale by Q. David Bowers
It is quite obvious from the above that another scale was desperately
needed by the hobby for indicating rarity of all coins. Leave it to Q. David
Bowers to recognize the need, and develop a method that could be used for
any series, and any rarity. In fact, this can be used not only with coins,
but with virtually anything when rarity, scarcity, or availability was
important. Bowers developed The Universal Rarity Scale (URS), which as its
name implies, is universal for any coin or item. Bowers outlined his scale
in the June 1992 issue of The Numismatist. It has already been adopted by
many writers and catalogers, including exclusive use in The Cherrypickers=
The URS is a reasonable mathematical progression. One does not need to
have a copy with him or her to be able to determine a correct URS. Just
simply remember the easy progression.
The Universal Rarity Scale
URS‑0 None known
URS‑1 1 known, unique
URS‑2 2 known
URS‑3 3 or 4 known
URS‑4 5 to 8 known
URS‑5 9 to 16 known
URS‑6 17 to 32 known
URS‑7 33 to 64 known
URS‑8 65 to 125 known
URS‑9 126 to 250 known
URS‑10 251 to 500 known
URS‑11 501 to 1,000 known
URS‑12 1,001 to 2,000 known
URS‑13 2,001 to 4,000 known
URS‑14 4,001 to 8,000 known
URS‑15 8,001 to 16,000 known
URS‑16 16,001 to 32,000 known
URS‑17 32,001 to 65,000 known
URS‑18 65,001 to 125,000 known
URS‑19 125,001 to 250,000 known
URS‑20 250,001 to 500,000 known
As you can see by the Universal Rarity Scale (URS), the mathematical
progression is simple, and can be applied to any item as an indication of
rarity. In addition, the scale, being simple, does not require memorizing
the scale, as one can figure what population a URS number indicates.
When using rarity numbers, with coins, there are a couple of important
things to remember. One, rarity generally differs from one grade to another.
If a coin is listed as URS 13 (2001 to 4000 known), it may be relatively
common. However, if there are only 2 known in grades above AU, it would be a
true rarity in
MS63. Such is the case with the 1888‑O Morgan Dollar, "hot lips" variety.
They are fairly common is VG and F, but virtually unknown above AU.
Secondly, rarity and value are not as closely related as one might suspect.
If there are 10 examples of a particular variety known, but only 7 or 8
collectors interested in obtaining a copy, the coin would certainly be rare,
but because of a relatively low interest factor, it would not command much
of a premium. Conversely, there could be many thousands of a variety known,
but if many thousands more collectors were interested in obtaining a copy,
the premium over the normal value of the coin would be greater due to the
high interest factor (demand). This brings us back to the old theory of
supply and demand.
Interest factor is a term used at times to indicate just how much demand
a particular coin or variety might have. A variety with a very high interest
factor would be in high demand, with several thousands of collectors
desiring the variety. A medium interest factor may indicate that the variety
is desired by hundreds or a few thousand people, and a low interest factor
might indicate that the coin is sought by just a handful of collectors.
The interest factor, combined with the rarity, help to determine the
value of a certain variety or error. However, the eye appeal of the variety
or error is also a contributing factor and must be considered in the final
evaluation. A very important part of eye appeal is the relative strength or
visibility of the particular variety or error ‑ how easily can it be seen?
As a variety receives more publicity within the numismatic press, the
Interest Factor may rise as demand increases. This may cause the price or
value of certain varieties (and errors) to increase without any change in
the estimated quantity available. On the other hand, if a large quantity of
a variety surfaces, the value of that variety may decrease as the supply
outstrips the demand.
As in other segments of the hobby, a combination of supply and demand
almost always dictates the price or value of a particular variety.
The Liquidity factor is a measurement developed by J. T. Stanton to
indicate how quickly or how easily a coin or variety should sell at auction,
given normal market conditions. Using a scale of 1 to 5, a Liquidity factor
of 1 would indicate that the coin would not normally sell very easily or
fast, and usually at a discount from suggested values. A Liquidity factor of
5 would be expected to sell right away, and generally command full or
inflated suggested values. Hot or highly active market conditions would
usually inflate the Liquidity of any coin, with a cold market causing the
RPM and OMM listing numbers
These are the original CONECA RPM and OMM listing numbers. You will
notice that most RPMs (repunched Mint marks) and OMMs (over Mint marks) are
identified simply, such as 1938‑D/S 5c, OMM #1. These numbers simply
indicate that the coin is a 1938‑D nickel, with an over Mint mark (D over
S), and is over Mint mark #1. This indicates that it was the first OMM
listed for that particular date by John Wexler and Tom Miller when they
originally produced The RPM Book in 1982. However, just because is was the
first listed, that in no way means that it is the strongest, the most
desirable, or the most valuable, although that is usually the case. The RPM
Book has become the standard in the hobby for RPM and OMM reference. Even
though published in 1982, it is still the most important reference for Mint
mark varieties as of the year 2003.
The same holds true for repunched Mint marks. If a coin is listed as a
1960‑D 1c RPM #1, it simply means that the coin is a 1960‑D cent, and is the
first RPM listed for the date. RPM #1 does not necessarily indicate that the
RPM is the strongest or the rarest, only that it was the first one to be
Doubled die listing numbers
As with the RPMs and OMMs, the doubled dies are also assigned numbers
which correspond to the listing numbers in the CONECA files. This numbering
system was developed by Alan Herbert and John Wexler. These numbers can be
confusing to the beginner, but the numbers have a very logical and important
sequence for the collectors, so a brief explanation is included herewith.
There are eight basic classes of doubled dies. These classes have nothing
to do with the strength of the doubling, but rather indicate how the
particular doubling occurred. Because of the complexity, the "how" is
covered in other references, and is not as important to most collectors as
is the strength of the doubling. For example, there is a Lincoln Cent listed
as 1971‑S PF 1c 1‑O‑II. These numbers indicate that the coin is a 1971‑S
Proof 1c, listed as die #1, with the doubling on the obverse, and it is a
class II doubled die. As with the RPMs, if the coin is die #1, it does not
necessarily mean that it is the strongest doubled die for that date, only
the first one listed. The sequence for these doubled die listing numbers
will always be the same. Following the date of the coin will be the
indication of a proof (if it is a proof), then the denomination, the die
number (indicated by Arabic numerals), an "O" or "R" signifying the doubled
die on the obverse or reverse, then finally the class of doubled die
(indicated by Roman numerals). There are some doubled dies which were made
as a result of a combination of more than one class such as 1971‑S PF 1c
2‑O‑II+V‑CW. The "CW" at the end indicates the spread (from the Class V
doubling) is in a clockwise direction. Class I and Class V doubled dies will
be indicated with a CW or a CCW, indicating either clockwise or
counter‑clockwise spread. There are also cases in which a coin will have a
doubled die on the obverse and reverse, such as 1963 25c 7‑O‑II +1‑R‑I. As
mentioned above, these identification numbers should become easy to
A more detailed description of each doubled die class is published in The
Lincoln Cent Doubled Die by John Wexler. This book is highly recommended for
all variety enthusiasts. Although published in 1984, it is still a valuable
source of information, and a must for variety collectors. These classes are
also published in The Cherrypickers= Guide, being included in the 3rd
Edition, the 4th Edition Volume One.
Other numbers are used from time to time usually to indicate a listing
number is derived from a reference book. A list of some of these reference
numbers follows. This list may not complete, as other books also have
reference numbers, and more books and reference works are being produced
BR (Briggs) Listed without a Briggs reference number in The
Comprehensive Encyclopedia of United
States Liberty Seated Quarters by Larry Briggs.
BL (Blythe) Listed without a Blythe reference number in The Complete
Guide to Liberty Seated Half Dimes by Al Blythe.
Breen Listed with a Breen reference number in Walter Breen's Complete
Encyclopedia of U. S. and Colonial Coins.
C (CONECA*) Listed with CONECA reference numbers in various locations
but primarily on the CONECA web site. (www.conecaonline.org) CONECA is the
acronym for The Combined Organizations of Numismatic Error Collectors of
F (Fletcher) Listed with a Fletcher reference number in Ed Fletchers
book The Shield Five Cent Piece.
FS (Fivaz/Stanton) Listed with a reference number in The Cherrypickers'
Guide by Bill Fivaz and J. T. Stanton.
LN (Lange) Listed without a Lange reference number in three references:
The Complete Guide to Lincoln
Cents, Second Edition by David W. Lange; The Complete Guide to Buffalo
Nickels, Second Edition by
David W. Lange; and The Complete Guide to Mercury Dimes, Second Edition
by David W. Lange.
Leone (Leone) Listed with a Leone reference number in Frank Leone's
Longacre's Two Cent Piece Die
Varieties and Errors.
LW (Lawrence) Listed with a Lawrence reference number in three
important references: The Complete
Guide to Barber Dimes by David Lawrence; The Complete Guide to Barber
Quarters by David Lawrence; and The Complete Guide to Barber Halves by David
SH (Sheldon) Listed with a Sheldon reference number in Penny Whimsy by
William H. Sheldon.
S (Snow) Listed with a Snow reference number in Flying Eagle and Indian
Cents, by Rick Snow.
VAM (Van Allen/Mallis) Listed with a Van Allen/Mallis (VAM) reference
number in the Comprehensive
Catalog and Encyclopedia of Morgan and Peace Dollars by Leroy Van Allen
and George Mallis.
WB (Wiley/Bugert) Listed with a Wiley/Bugert reference number in The
Complete Guide to Liberty Seated Half Dollars by Randy Wiley and Bill Bugert.
NOTE: Other attribution numbers and/or notations may be added in the near
Copyright 2005 by J. T. Stanton.
J. T. Stanton
P. O. Box 15487
Savannah, GA 31416-2187