Stamps (Philately)/gripper cracks


Hello Terry!

I was impressed by your years of experience and offer to assist as an expert.  I have a number of plate block # MNH blocks of four and six of #728, the well known green Deerborn "century of progress" stamp.   The Scott catalogue says that plate block #21133 has something known as "gripper cracks" and that gives a higher premium.
   My 3 questions are:  I have three groupings marked #21133.  Where are the gripper cracks?  What are they? and are they on every stamp from that block?  I have good magnification lenses if that is needed for identification.

A gentlemanly thank you in advance for your help-

John Morgan

Hello John,

Thanks for your question.

The best way to answer "what are gripper tracks" is to quote PNC Glossary:

"A form of plate variety that occurs along the top or bottom row of stamp subjects on a printing plate. Tension cracks occur on printing plates most frequently where the grippers hold the curved plate to the cylinder. These cracks collect ink and deposit it on the printed stamps. Gripper cracks look just like a crack, jagged line, or series of lines running through the stamp design."

If you go to their web site, they have some beautiful examples of gripper tracks. And no, they are no on every stamp in that block.


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Terry Tipton


I have been involved in philately for most of my 56 years. I specialize in United States Issues and Postmarks. I have numerous reference sources to research if I do not know the answer. I am organized and promise swift courteous answers. I am a member of the American Philatelic Society. I also have my own philatelic mail order business.


As I mentioned, I have been collecting philatelic items for most of my 56 years. I have several albums of United States issues (most of them are pages I designed myself) and I also have numerous albums of postmarks sorted and researchhed by state.

American Philatelic Society, All Nations Stamp Club and Harford County Stamp Club

Linn's, All Nations Stamp Club Website, and local Newspaper

Awards and Honors
Board of Directors for Christmas in April 1990-1996

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