Technology and Terminology of Knapped Stone - IRIT

• "Square cross-section" stone axes of the Danish Final Neolithic
The preforms of axes with a square cross-section (fig. 18 : 1) are prepared in the
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following way : after some preliminary flaking of the block (chosen in relation to the
anticipated size of the final product), the roughing out of the quadrangular shape is carried out
by direct percussion with hammerstones whose weight will vary according to the different stages
of the work. The shape of the roughout must be as close as possible to the ultimately desired
morphology, because subsequent "corrections" are fraught with difficulties. The next step is the
trimming of the preform, carried out by indirect percussion with a punch. Giving a regular shape
to the ridges of the preform, which must be perfectly rectilinear, is done by applying light blows
with a soft hammer, or by using indirect percussion or pressure. The preform is then ready for
polishing, the latter being carried out by hand for small axes, or on a large polishing stone with
a specific device for axes more than 20 cm long 51
. The whole process thus entails at least three
different techniques.
• Egyptian predynastic knives
Another example, drawn from protohistoric times, is the complex chaîne opératoire of
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the Egyptian predynastic knives of the Gerzean period (about 3200 years BC) , which involves
the following steps : preliminary flaking of a block or slab of flint ; roughing out and careful
preparation of the preform (using direct percussion with a soft hammer for the latter two
operations at least) ; polishing of the entire preform, which can be as long as 30 cm ; preparation
of the edges ; application of pressure (probably with a copper instrument) to retouch one of the
faces - the other remains polished - thereby producing long parallel S-shaped removals (ripple
flakes), whose aesthetic function cannot be denied ; fine denticulation of the working end.
• Polished axes from Irian Jaya (Indonesia)
A remarkable ethnographic example of chaînes opératoires concerned with the fashioning
of polished axes and adzes has been recorded in Papua New Guinea 53
(fig. 18:2). In the
west-central valleys of Irian Jaya, there exist groups who still manufacture axe, adze or chisel
"blades", applying four techniques whose ordering varies according to the raw materials and the
technical abilities of each group : flaking (using direct percussion with a hard or soft hammerstone,
or percussion on an anvil), pecking, polishing and sawing.
Following the collective procurement of the raw material, a process that can involve
selective collecting, quarrying (digging of funnels or pits) or thermal shock (fire induced
fragmentation), the main techniques (or combinations of techniques) used are : elaborate flaking
and minimal polishing ; minimal flaking and intensive polishing ; minimal flaking or summary
sawing and pecking, and intensive polishing ; pecking only ; sawing only ; polishing only.
Once finished, the blades are variously hafted with wooden handles to make axes or
adzes. Used for hewing down trees and splitting wood, these tools also play an important role in
the exchange system and possess a highly symbolic value.
• Knapping of carnelian beads in India
The knapping of carnelian beads and trinkets is still practised today in Khambhat, in the
Gujarat (India), and is very interesting from an ethnoarchaeological standpoint, in relation to
archaeological data dating back to the third millenium of the Indus civilisation. Indeed, it has
been possible to compare the contemporary workshops directly with some archeological
workshops recovered from Chanhu Daro and Lothal 54
.
The present day production line is the following 55
. Vertical pits sometimes 15m deep
are dug into the fossil terraces of the Narmada (more than 100 km away from Khambhat), from
which carnelian cobbles are quarried and then selected according to their size. They are
heat-treated in order to improve the knapping characteristics of the stone, and can be subjected
to the same treatment a number of times at any and all stages of the chaîne opératoire to alter
the red of the carnelians. Knapping involves two steps, roughing out and making the preform
50 Hansen, Madsen, 1983.
51 Madsen, 1984.
52 Midant-Reynes, Tixier, 1981; Kelterborn, 1987.
53 Pétrequin, Pétrequin, 1993.
54 Mae Kay, 1943; Rao, 1973.
55 Roux, Pelegrin, 1989.
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