Stone Sarcophagus Manufacture in Ancient Egypt
Stocks, Denys A., Antiquity
The creation of sarcophagi from single blocks of stone, particularly the hard, igneous varieties, was accomplished by the development of stone sawing and drilling skills: the saws and drills for working hard stone, and indeed illustrations of the processes, have never been discovered by archaeologists. An examination of ancient sarcophagi, particularly the tool marks left on them, helped reconstruct copper saws and tubular drills for test on different types of stone. Stone sarcophagi were also carved with hieroglyphs and reliefs, both internally and externally. These techniques were investigated by comparing the relative capabilities of replica copper, bronze and iron chisels to reconstructed flint chisels, punches and scrapers for cutting different stones.
Monolithic stone sarcophagi were first introduced in the Third Dynasty (c. 2686-2613 BC), being constructed from soft white limestone (hardness Mohs 2.5) and calcite (Egyptian alabaster, Mohs 4). In the Fourth Dynasty (c. 2613-2494 BC), Cheops' (c. 2589-2566 BC) craftworkers manufactured the first sarcophagus of granite (Mohs 7), an igneous stone. Subsequent sarcophagi were made from these three stones, along with basalt, quartzite (both Mohs 7) and greywacke (Mohs 4-5). Soft limestone, calcite and granite represent ascending degrees of difficulty in making sarcophagi; consequently, these stones were experimentally sawn, drilled and cut in investigating ancient shaping, hollowing and relief carving techniques by ancient stoneworkers.
Shaping stone sarcophagi and surface decoration tools and techniques
Assessments of the performance of ancient copper and bronze chisels, traditionally thought to cut hieroglyphs and reliefs into stone, were made by experimenting with replica copper, leaded bronze and bronze chisels (Stocks 1986c: 25-6). They demonstrated that all stones of hardness Mohs 3, and below, could speedily be cut, including soft limestone. However, stones of Mohs 4, and above, cannot efficiently be cut by such metal tools; test tools' cutting edges were blunted, or torn away, to such an extent that constant sharpening, even for cutting calcite, caused unacceptable losses of metal from the tools. Other experiments (Stocks 1986c: 26) revealed that iron, or even steel, chisels were useless against igneous stone, such as basalt and granite, suffering considerable damage to their cutting edges.
Tests with dolerite and diorite tools by R. Engelbach (1923: 40) and A. Zuber (1956: 195) indicated a poor ability to cut granite. Zuber (1956: 180, figures 18-20) cut granite with flint (Mohs 7) implements, and my own experiments with flint chisels, punches and scrapers on granite, diorite, hard and soft limestone, hard and soft sandstone and calcite (Stocks 1986c: 25-9; 1988: II, 246-73, plates XXIV, b, XXV, b) revealed that flint tools can satisfactorily work all these stones, but that the cutting of igneous stone is a slow process. These findings support the shaping and hollowing of soft limestone sarcophagi by copper adzes and chisels, but it is possible that these sarcophagi were also worked by flint chisels, adzes and scrapers (Petrie 1938: 30). Flint chisels, punches and scrapers were necessarily used to carve hieroglyphs and reliefs on the internal and external surfaces of hard stone sarcophagi (e.g. the recessed palace-facade panelling on the Fourth Dynasty rose granite sarcophagus of Prince Akhet-Hotep, Brooklyn Museum 48.110; incised hieroglyphs inside greywacke and granite sarcophagi, Musee du Louvre N345 D9, N346 D10), and also to shape anthropoid sarcophagi from the Middle Kingdom onwards.
There are chevron-shaped sawing marks on Sekhemkhet's calcite sarcophagus (Goneim 1956: 108), and linear striations, or grooves, on the sides and ends of Cheops' granite sarcophagus, and other hard stone objects located at Giza (Petrie 1883: 174-5, plate XIV, 1, 2). These striations, and other evidence for copper saws and tubular drills in use with sand abrasive (Petrie: 1883: 174-5; Reisner 1931: 180; Lucas 1962: 74), indicate that a flat-edged copper saw cut Sekhemkhet's and Cheops' sarcophagi to shape. …