Technology and Terminology of Knapped Stone - IRIT

Bifacial shapin g
Bifacial shaping appeared in eastern Africa at the end of the Oldowan period, more than
one and a half million years ago, and has virtually always been used ever since. The handaxe is
an all-important feature of the Lower Palaeolithic. Although not omnipresent, it is - sometimes
along with the cleaver - the best represented tool in Acheulean industries. It remains conspicuously
present during the Middle Palaeolithic. In later periods, bifacial shaping appears or
disappears depending on the culture. In the French Upper Palaeolithic, for instance, it reaches its
apogee with the Solutrean, but is not taken up later by the Magdalenians. On the other hand, in
other cultural contexts, such as Asia, bifacial shaping features in the technical background during
the entire Upper Palaeolithic. As from the end of the Mesolithic and until metal appears, it
becomes virtually universal owing to the development of projectile points.
1. Methods
Although the methods used for bifacial shaping vary considerably according to the
different periods, the basic concept stays much the same. Differences appear only within the
operative schemes, the techniques and the way in which they are applied. The bifacial concept is
described here from a general point of view.
Whichever way the original blank was obtained (it can, for instance be a large flake
struck off from a core), bifacial shaping can be divided into two phases, roughing out and
finishing.
• Roughing out consists in the simultaneous fashioning of two more or less convex
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surfaces on either side of a bifacial equilibrium plane (fig. 11 : A). This term is used in
preference to plane of symmetry because the two surfaces - which define a contour, marked out
by a ridge - are definitely not always symmetrical, and this applies in particular to handaxes.
• Finishing consists in giving the contour a regular shape, according to a second bilateral
equilibrium plane (fig. 11 : B), perpendicular to the bifacial equilibrium plane. Finishing bears
some similarity to retouching, especially where small pieces made from flakes are concerned. It
is this step that gives the artefact its final morphology, by delineating the edges, carving out a
tang, or arrowhead wings, etc.
Any blank can be shaped into a bifacial piece : a cobble, a block, a slab, a chunk of stone,
and of course a flake (fig. 8). The closer the morphology of the blank is to the intended final
shape, the less work is required to rough it out. In the case of a bifacial piece made from a thick
block, it is necessary to do some preliminary flaking before roughing out can be undertaken : this
entails flaking away the cortex and coming closer to the desired morphology. On the other hand,
one or two generations of removals only are needed to shape a bifacial piece made from a flake.
Some Acheuleans have systematically struck off large, short and wide slightly déjeté flakes, to
use as blanks for their handaxes : in that case, shaping is incorporated into a longer chaîne
opératoire, which includes an initial flaking sequence that shows predetermination in the
obtaining of blanks 44
.
2. Technique s
Prehistoric people applied the main stone-knapping techniques to bifacial flaking as they
successively invented or adopted them : direct percussion with a hard or soft hammer, indirect
percussion, pressure, pecking, and then polishing.
As early as the middle Pleistocene, different techniques were brought into play for the
fashioning of a single bifacial artefact : direct percussion with a stone hammer to first remove
the blank and then rough it out, direct percussion with a soft hammer to give the piece its final
shape. These two operations generate characteristic flakes (fig. 14). The shift from one technique
43 Texier, 1989; Roche, Texier, 1991.
44 Texier, Roche, 1995b.
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