100 Kroner Heilmann type II

Gerhard Heilmann was primarily known as an ornithologist — his 1926 book on the origin of birds remains a landmark in paleontology — and the Nationalbanken's decision to commission him for banknote design was an unusual one. His work on the Danish series has a naturalist's precision to it, which set it apart from the more conventional academic engraving that dominated European note design in the 1920s and 30s.

Four signature combinations across six years reflects genuine administrative turnover at the bank, not printing anomalies. The Lange & Jessen pairing from 1930 is the earliest and typically the harder of the four to locate in collectible condition, as first-year notes from this series saw heavier counter use.