This chert blade is from Europe.  It likely dates from the late Mesolithic or Neolithic periods, ca. 9000-5000 BP.

The artefact is curated by the Australian Institute of Archaeology, catalogue no. IA24.191.

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This blade is from Europe but the precise provenance has been lost.  It is made from a translucent chert with abundant marine microfossils.  The surfaces are patinated milky-white, which is common for silica-rich flints and chalcedonies.  The technique used to produce this blade is ambiguous.  The blade was removed from a bidirectional core and the outline is slightly irregular, with one straight margin and one flaring outward towards the distal end.  The blade’s profile is slightly twisted.  These attributes suggest an indirect percussion technique was used.  However, the platform is exceptionally small and somewhat acute, and the bulb of force is rather short and defined by a prominent undulation.  These attributes suggest detachment using a pressure technique.  The distal end of the flake is truncated by flaking, probably at the time it was used, and both edges show micro flaking, perhaps from use-wear.

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In archaeological terminology, a ‘blade’ is a flake struck down parallel ridges on a core face, and measures at least twice as long as it is wide.  The edges of the blade are approximately parallel.  The core face is maintained by prior removals, and blades are struck off in series.  If they are struck from one platform, the removals are ‘unidirectional’, and if they are struck from two opposed platforms, they are ‘bidirectional’.  Blades were struck by direct percussion (using a hard or soft hammer) or indirect percussion using a punch; or they were pressed off using a pressure technique.

Indirect percussion involves placing a punch on the platform edge of the core and detaching the blades by striking the end of the punch.  By using a punch, the flintknapper can precisely manipulate the placement and angle of the blow that initiates fracture.  Punches made from curved tines of red deer antlers were found at an Ertebølle phase site called ‘Grube-Rosenhof LA 58’, located in northern Germany.

The pressure technique involves placing the end of the indentor onto the platform edge and applying a load—either by hand or using a lever—until the crack initiates.  The placement of the indentor and the amount of applied force can be precisely controlled, resulting in extraordinary control of the size and shape of the resulting pressure blades.  A common approach was to set up the core so that most of the blades had a trapezoidal cross section; these are called ‘prismatic’ blades.  One of the trickiest aspects of pressure blade-making is securing the core, and experimental flintknappers have devised various ways to do this.  Pressure blade-making was famously explored by the experimental flintknapper Don Crabtree in the 1970s.