Tonga 1891 8d on 2d violet variety, SG6aTonga 1891 (10 Nov) 8d on 2d violet, type 4 surcharge, horizontal pair, the right stamp showing variety "Short T in EIGHT", SG6a. A fine and fresh mint pair with large part original gum. Only 50 sheets were surcharged and the variety is very scarce, particularly as a pair and in such fine quality. The Stanley Gibbons catalogue value is 215+. Tonga became a constitutional monarchy under King George Tupou I (named after King George III), in 1875. Stamps