Denmark – Scott #s 409-10, hinged

Description

Issued by Denmark in 1963, this two-value set (Scott #409–410) commemorates the 50th anniversary of Niels Bohr’s atomic theory (1913–1963). Each stamp features a portrait of the Danish physicist alongside a stylized atomic model and the key energy-level equation hν=E2−E1h\nu = E_2 – E_1hν=E2​−E1​, referencing the quantum leap principle that reshaped modern physics.

The 35 øre appears in a rich reddish tone, while the 60 øre is printed in deep blue, both engraved with crisp detail characteristic of Danish commemoratives of the period. These examples are unused hinged, showing fresh color and light gum disturbance consistent with hinging. A classic scientific set with strong topical appeal in physics, Nobel history, and mid-century European design.