As a young man I learned how to identify sheet varieties by the appearance of the perforations alone.  Perforations of course, are the holes punched between postage stamps to make separation easy.  I found myself in situations where I didn't have a perf gauge handy but still wanted to search stamps for varieties. Not everybody knows that perf varieties can usually be determined without a perforation gauge!  The result for me was a nice accumulation of better varieties like 1596d, 1622C & C98A.  This short guide exposes the relationship between the way perforations look and their gauge measurement.  In a future article we will discuss self-adhesive die cutting.

There are 3 basic types of perforation varieties on modern water-activated (gummed) stamps.

Bullseye Perforations

Bullseye perforations are known by many names including "Harrow type" "in line" and "on press."   They are perforated in one step with all holes coming together perfectly at intersections.  The selvage margins are NOT perforated.  The perfs usually measure 11.2 x 11.2, but are frequently rounded to 11 x 11.

All 4 corners of bullseye single stamps always look like this.    I call them "dog bone" corners.  With a little practice they are unmistakable from all other types, which are irregular shaped.

L Perforations

These are perforated in a 2-step process.   The holes are punched in an L shape and then turned 90 degrees and punched again.   This results in overlapping holes that do not usually come together as they cross.   All of the margins are fully perforated.  The perfs measure 10.9 x 10.9 and are usually rounded to 11 x 11.

Occasionally 1 or 2 of the holes will line up to look like bullseye as the photo shows.   Inspecting the other 3 corners of the stamp will reveal the true gauge to be L (NOT B perf.)

EL Perforations

Electric eye "L" type perforations (EL perfs) appear the same as L perfs but do not pass all the way through the selvage.  This is handy when cherry-picking EL sheets like 1580B.  Look for L perfs that don't extend through the margins.  The perfs measure 10.5 x 11.3 (often rounded to 10½ x 11 or 11¼).

How is this useful?

Below are just a few examples of ways that you can benefit from this information.

Scott 1735 the orange "A Rate" eagle stamp has 2 varieties that both measure approx 11.   The L perf variety has the catalogue number 1735 while the B perf variety has the catalogue number 1735c.  They can be easily distinguished by perf type, but otherwise you'd need a "Multigauge" tool to see the differences in the exact measurements.

Scott 1711 Colorado Statehood has 2 varieties with significantly different values.   The L perf variety has catalogue number 1711 and the B perf variety has number 1711c.   Plate blocks of 1711c are valued at 3 times the price of the common counterpart.  Often these are sold without the owner bothering to determine the differences.   

Scott 1580 Prang Christmas stamp has been known to cause headaches because of the 3 different varieties.   Identification is actually quite simple.  The bullseye perf variety is 1580, the L perf variety is 1580c, and the EL perf variety is 1580B.  The 1580B plate block has a catalogue value that is 3 times the price of the others!  If you know the secret, you may still find the more expensive stamps at the same price as the common ones.

Often perforation varieties are accompanied by differences in tagging and gum and are helpful in validating the appearance of these other indicators.

This is a list of gummed sheet stamps that have more than one perforation type and catalogue number:

1580 =B, 1580B =EL, 1580c =L

1596 =B, 1596d =L  *scarce

1622 =B Huck Press, 1622C =B Giori Press

1711 =L, 1711c =B

1735 =L, 1735c =B

1789 =Perf 11 x 12, 1789A =Perf 11, 1789B =Perf 12 x 12  ***extremely scarce

1795-1798 =EL, 1795a-1798a =B

1844 =B, 1844c =L, 1844d =L

1862 =L, 1862a =B, 1862b =B, 1862d =B

1863 =L, 1863a =L, 1863b =B

1864 =L, 1864a =B 1864b =B

1867 =L, 1867c =L, 1867d =B

1868 =L, 1868a =B

1869 =L, 1869a =B, 1869d =B, 1869e =B

1894 =L, 1894e =B

1951 =B, 1951A =EL

1953-2002 =EL, 1953A-2002A =B

2524 =L, 2524A =B

2535 =B, 2535A =L

C98 =B, C98A =EL

C105-C108 =B, C105a-C108a =L

C128 =L, C128b =B

C129 =L, C132 =B (Piper has different numbers but also perforation and tagging differences)

The tagging types are not listed here.  Check your catalogue for detailed information and pricing.  You might be surprised!   If you know of any other numbers, please contact us to update list.

STAMP TIP!

Every week on eBay we see minor number sheets, plate blocks & singles lumped together as the major number variety.   Catalogue values are rarely the same.

**Be sure to FIRST contact the seller and clarify.  Sometimes uninformed sellers will picture a rare variety but send a common one after you buy it. **

Make a habit of familiarizing yourself with minor numbers in your catalogue.  I teach my students that knowledge is power.  Increase your expertise and awareness and someday you may be smiling as you pull that elusive sheet or block from a dealer's postage box or online discount auction.

Congratulations!

If you are still reading then you have just passed PERFORATION 101.

We sincerely hope you fine this guide useful.  Please contact us at any time with comments or suggestions.  Revisions can easily be made.

Your positive vote will encourage us to write more. 

Thanks for looking!

-TBR

MY EBAY GUIDES