Bifacial and unifacial technology: A real difference or a problem of typo-technological approach? The example of the Ehringsdorf assemblage

Discussion of differences and possible links between bifacially and unifacially shaped tools has quite a long tradition. Certain techno-complexes are distinguished due to the presence or absence of bifacial technology (e.g. Keilmesser group, MP/UP transition leafpoint industries). The paper draws attention to a problem of defining bifacial and unifacial technology. The Ehringsdorf (Germany) tools show traces of multiple, subsequent resharpening. The knapper started from unifacial retouch on one or both edges of a flake's dorsal side. In the course of further resharpening, the ventral side of the flake required certain adjustments. After several rejuvenation phases tools show all the features of bifacially shaped tools in a type of leafpoints or knives. From a technological point of view, the question arises if such a reduction sequence can be called bifacial, unifacial, or should be defined in a different way.