Papua 1930 'Air Mail' 1s sepia and olive, Harrison printing, type 11 overprint, ERROR OVERPRINT INVERTED, SG117a.
A very fine mint example of this famous error with original gum. An exceptional example of this dramatic error, with the plane "looping the loop".
Sanabria hand stamp on reverse as is the usual.
Only one sheet of 40 existed and they are seldom seen on the market. This is the first time we have experienced the privilege of handling one.