This is a vintage example of the iconic K55K Panther Mercator folding knife, produced in Solingen, Germany—a city renowned for its blade-making tradition. With its slim, all-steel construction and simple lock-back mechanism, the Mercator knife has earned a reputation for rugged reliability. This model is stamped K55K beneath a leaping panther on one side of the handle, with MERCATOR – GERMANY on the spine and MERCATOR and SOLINGEN stamped on the ricasso of the blade.
First produced around 1867 by Heinrich Kaufmann & Söhne, the K55K became widely known as the "Panther Knife" or sometimes the “Black Cat Knife” (especially in export markets). It was especially popular during and after WWII, often brought home by soldiers as a souvenir.
Based on its markings, construction, and finish, this K55K Panther Mercator knife likely dates from the late 1940s to the 1960s. The dual Mercator and Solingen blade stamps, along with the all-steel unpainted body and riveted construction, are consistent with post-WWII production by Hy. Kauffmann & Söhne, prior to the brand’s acquisition by Otter-Messer. While exact dating is difficult due to the knife’s long and consistent production history, these features point to an early postwar example rather than a more recent reproduction.
Approximate Measurements: Folded length: 11 cm
Blade length: 8.4 cm
Overall open length: 19.5 cm
*Condition*
The knife shows age-consistent wear, with general surface corrosion, patina, and loss of finish across both handle and blade. Markings remain legible despite the oxidation. The blade retains its original profile and opens and locks securely. The mechanism appears to function correctly, though the piece is best suited for collection or restoration. An authentic example of a historically significant German pocketknife. Please refer to photographs as part of the condition report.
