Blind perf

Blind perfs are when perforator pins fail to punch through stamp paper but leave an indent or indents instead. If the paper remains untouched, it is likely a true partial imperf, a genuine error. However, if even part of dent is detected, the stamp is judged to have blind perfs, and then falls into the freak/oddity zone with perhaps a very small premium.

Stamps have been known to be cut by forgers with a straight edge over a line of blind perfs to look like one side is imperf.  File:Saur clean 1a.A.webp|Lots of blind perfs here on this stamp of Saurashtra/Soruth. 

[[Category:B]]