Reply To: Imperial Arms Issue 1909-12, 1912-1918

David Jay

Horizontally wove paper was used in 1909 and in 1910-1911. Vertically wove paper after that.
This is easiest to see from the back of the stamp. Color can be helpful, but is treacherous — particularly for the 10k blue. Blue fades easily, at least that blue ink did. I’ve also found catalog values to be rather arbitrary — the 1909 10k blue, for example, is much more common than usually thought.