5h light green – spot at 46/1 (the “grape cluster”)
A well-known smear occurs on the 5h light green (POFIS no. 3), stamp field 46/1 – known among collectors as the “grape cluster” (hrozen).
This production flaw was caused by a foreign object sticking to the printing plate during printing. Here too you can see the initial state, when the object is on the plate and the ink adheres to it – the result is a coloured (green) spot with a white border. The next phase is a white spot only: the object came off the plate, but the spot probably remained greasy and would not take ink. As printing continued, the smear gradually shrank.
Detail of the development of the flaw:
