Glossary of Flaws & Errors in United Kingdom Stamps

SG:

Stanley Gibbons Error Reference

ND:

Newly Discovered Error or Not Documented Reference

BMB or RMB

Black or Red Mark on the Booklet

STAMPa

Errors documented by Stanley Gibbons (SG).
Pane Number UMFB2 or Stamp Number followed by small letter a-z

STAMP-xe1-

New Errors Found and documented by the collector. 
Pane Number VB3d followed by -xe1 to -xe999

STAMP-yRPS

Right Phosphor Shift

STAMP-yLPS

Left Phosphor Shift

PIPP, PIPI, PPPI

P = Perforations, I = Straight Cut

WR, CR

WR = Incorrect Rates, CR = Correct Rates

Perforation Margins

For Identification of Perforations, the Booklet must be viewed with the margin at the left.
Right Margin Booklets must be viewed upside down.

Phosphor Bands position
described by Deegams

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