| These pages will describe the basics of making and studying stone artefacts. To extract information from stone artefacts you must learn about how they were made and how they can be studied. Today the art of stoneworking is unfamiliar to most people, and the purpose of this area is to give you an understanding of the study of stone artefacts. |
| The process of making stone artefacts, often called 'stoneworking', 'flaking' or 'knapping', is at its most basic conceptually simple. The only form of stoneworking examined here is the shaping of artefacts through the conchoidal fracturing of rock. Fracturing is begun when sufficient force is applied to a suitable rock. The force can be applied as a gradual pressure (called 'pressure flaking') or as a sharp blow ('called percussion flaking'). Percussion flaking is accomplished using a hammer, such as the symmetrical cobble on the right, which has marks of battering at one end.
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| | When the fracture has been completed there are two pieces of stone. The smaller piece is called a flake. The surface of a flake created by the fracture is called the ventral face and this contains a series of distinctive fracture features, such as those that can be seen on the flake to the right. These features are given standard labels which provide the essential jargon by which archaeologists describe the flaked artefacts they find.
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| | The larger fragment left behind when a flake is removed is often called a core, although it is also possible to strike a flake from another flake, which is then called a retouched flake. The photograph on the right shows a core. When flakes are removed from a core or retouched flake they leave negative scars (or flake scars) that are the reverse image of the ventral surface. These scars are evidence of the flakes that have been removed.
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| One of the most important ways in which stoneworkers control fracture is their selection of raw material. Suitable rocks for making artefacts by flaking are those that are homogeneous, isotropic, and hard. Many siliceous rocks such as chert or quartzite are ideal. Stoneworkers also choose between nodules of different sizes and shapes, so that they minimise problems by selecting the raw material most suited to their needs. At quarries, where stone is procured it is common to see flakes removed by knappers who were testing the suitability of rocks.
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| Stoneworkers also control the production of artefacts by artificially altering the properties of the rocks they have. This can be done in a number of simple ways, such as warming the rock in the sun or soaking it in water. But the most dramatic improvement in the properties of rocks is obtained by controlled heat treatment which effectively makes the rock more homogeneous (see the before and after photographs to the right).
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| Stoneworkers control the outcome of fracturing rocks in a number of additional ways:
1. by shaping the surface of the rock about to be struck, and by selecting the surface on which the blow is placed,
2. by varying the amount of force and direction in which it is applied.
3. by selecting hammers or pressure flakers with different weights and different shapes.
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| While these principles are straight forward, archaeologists must be careful not to mistakenly interpret all broken rock surfaces as a product of human artefact manufacture. Several other process superficially imitate the scars left behind by flakes. However those scars can be distinguished from flake scars on a close inspection. An example of such potentially misleading processes is the heat shattering of rock.
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peter.hiscock@anu.edu.au.