5 September 2026
Imperforate and numbered: how to spot a rarity
An imperforate sheet is a variety without perforation, usually in a small run. A numbered block carries a printed serial, making each copy unique. Both are prime targets for the modern collector.
On every card we show the print run where it is known — often a few hundred copies. Rarities have their own section, and the Michel number-range filter helps you pinpoint exactly what is missing.