Aitutaki 1919 (Sg 23) Joined Pair Mystery

Would anyone like to hazard a guess at why these two stamps were joined?

As far as I'm aware, the only reason this is done is to create coil strips, which could be the case here, as the lower stamp shows that it was joined to the stamp below in the same manner.

However, Gibbons does not list a coil for Aitutaki. Which doesn't mean the postmaster there didn't make his own!

Thoughts anyone?

these are just 2 stamps on piece; stuck close together..

I concur, if they were a joined pair the bottom one would have full perfs and it's paper would run under the top one.

Actually, they're not. But the scan doesn't show the join as clearly as can be seen clearly with the naked eye. There is a strip joining the top stamp with the bottom stamp and the bottom stamp has a portion of the same kind of strip at the base. This is the down side of using a scanner.

It does not look like a coil join. Unless the government printers in New Zealand pasted up rolls of stamps in another way than most British Empire printers, the paste-up would have one strip being joined on the margin of another strip. The 'join' appears to have been made by applying a piece of translucent paper under both stamps after perforating. Also, the same paper appears to have been applied on all four sides of the bottom stamp. It looks like someone, at some time, tried to (re?)construct a multiple.