This is a backed knife from an MTA context in Northern France (Fig. 1-3; 6x3x0,5 cm). The retouched margin is shown in Fig. 3.
Interestingly this artifact was found in the Paris area by a collector, during the years 1905-1910 with some other non-diagnostic blanks, in the Bois de Boulogne.
Middle Paleolithic industries with backed knifes in Northern France are known since the Upper Acheulian before MIS 5 but occurred more frequently during the MTA at the beginning of the last glacial (Marcoing, Catigny, Tillet- série café au lait, Abri de la grande chambre à Rinxent).
Backed knifes from the MTA were made on flakes or laminar blanks. On laminar blanks a typical backed knife has a steep abrupt retouche on one side, continuously covering the margin. Backing is inevitably connected with the function of this special retouche. Backed artifacts, either used by “free hand” or as hafted tools, are designed for cutting with the opposite edge. This is one of the scare examples of an intended form connected with an obvious and micro-traceological proven function during the Middle Paleolithic of S/W-Europe
Many tools that were introduced in the literature since F. Bordes as Mousterian „knifes” have fine marginal, often semi-abrupt retouches, but no backing in the original sense. I would call them marginal retouched blades or flakes. Such retouches do not allow to use these artifacts as knifes by free hand, and it remains to be proven experimentally that such retouches have any advantages for hafting.
“What difference does it make what I call it?” Naming things properly is important in the Archaeological discourse, because a careless nomeclature inevitably will produce biased data.