This is a more unusual item when it comes to plate block collecting. This is the 13¢ Captain Cook issue from 1978. On this pane of 50 stamps, 25 of the stamps depict Captain Cook. The other 25 stamps depict his ship, the Resolution. Only in the center of the pane do the two stamps meet to create 5 setenant pairs. Unlike most other setenant issues, a plate block of four in the corner shows only one of the stamp designs, but not both.
What constitutes a plate block on this issue? There are three possibilities.
First is a corner block/4 with plate number with just Scott #1732.
Second is a corner block/4 with plate number with just Scott #1733.
However, these corner blocks don’t show the complete set of stamps as a single unit. You only have one stamp design or the other. As blocks/4, it seems that these stamps came from different panes and not from a single pane. For collectors who only want a plate block/4, they will collect a plate block of each design.
Because the stamps were issued on the same pane, some collectors want a plate block to show both designs. The third option is to collect a plate strip/20 so that it shows both designs together.
Which one is correct? They all are correct.
Some collectors like the smaller blocks/4 and having both blocks of #1732 and #1733 is fine with them. Other collectors prefer the long plate strip/20. In my experience, most customers tend to go for the full strip/20 because they want to show that both stamp designs are part of the same pane. I encourage you to collect them the way the suits you. Don’t let anyone convince you that one format is the only correct way.