The blade shows the typical hallmarks of the “en eperon” technique (EPT), which was first described by Cheynier in 1956. This technique refers to a special method of platform preparation used in the manufacture of long regularly blades and leaves characteristic flake scars on the butts of individual blades.
An eperon butt is characterized by two series of small convergent removals isolating a spur. The butt is also often steeply inclined with an acute angle de chasse (the angle between the main flaking face and the butt surface). Experienced knappers suggest that this technique is especially helpful to detach long, straight blades in a controlled and consistent manner by direct soft hammer percussion. It remains unclear if the en eperon technique is a “tradition” or an inevitable recurrent re-invention during the upper Paleolithic. Maybe both hypotheses are true.
The preparation of en éperon type blades from unipolar cores, correlating with the rejuvenation of the platform by tablet detaching has been described as one typical finding of the Aurignacien ancien classique in S/W France (for example at the site of Barbas II in the Dordogne). During the Aurignacian the EPT was not confined to S/W France, as recently reported from the open air site at La Croix de Bagneux (Mareuil-sur-Cher).
The EPT is absent in the French Gravettian, but has been extensively described from the “Protomagdalenian” levels at Le Blot and from other “Protomagdalenian” sites (Laugerie, Pataud). I personally do not know any data about blades en eperon during the Pavlovian, Willendorf-Kostenkien or the Epigravettian.
While in France the use of the EPT was rare during the Badegoulian (Badegoulian type La Croix-de-Fer) and early Magdalenian, there is a cluster of sites during the late Magdalenian, roughly beginning at 13000 BP during the end of the older Dryas. Evidence comes from the Paris vicinity (Etiolles, Pincevent), the Rhine (Andernach and Gönnersdorf) but also from rather peripheral sites like Duruthy (Landes) and Klementowice (Poland). The EPT has been described from Creswellian and even Hamburgian ensembles, thus indicating their possible roots in the Magdalenian complex sensu lato.
Suggested Reading: http://paleo.revues.org/908