Great Britain 1972 Royal Silver Wedding 3p unmounted mint traffic light corner block of 15 with numerous white spots probably caused by a cleaning solution splashing onto the printing plate, affaects at least 8 stamps but is parti……Details Below

Great Britain 1972 Royal Silver Wedding 3p unmounted mint traffic light corner block of 15 with numerous white spots probably caused by a cleaning solution splashing onto the printing plate, affaects at least 8 stamps but is particularly noticeable on 4th stamp on top row, most unusual