The transition between a plate block of six with plate number in the middle (old format) mostly for flat plate stamps and a plate block of four with plate number in the corner (new format) mostly for rotary press stamps occurred in 1922. U.S. Scott 543 is a rotary press sheet stamp that was first issued with the old format in 1921 and with the new format in 1922. The first rotary press sheet stamp was issued in 1920 and it is Scott 542. Scott 542 was the only rotary press sheet stamp that was issued only in the old format. Flat plates had the old format until around 1940. Today, the popular four square corner plate block new format that many stamp collectors collect as matched sets all over the world was due to this. The first plate numbers were 13744 and 13745 since rotary press stamps were printed two plates paired together at a time. Over time, the four corner number plate block was used for other printing presses too including flat plate, Giori, photogravure, lithographed, etc. printed stamps. Thus, it deserves our admiration and respect as a philatelic first, especially from collectors of corner number plate blocks.
Posted 06/17/2013 08:56 am
