Wednesday, 2 April 2014

Copper awl points to non-local origin for metallurgy in southern Levant

Artefact was imported centuries before Late Chalcolithic.

The southern Levant became a major centre for metallurgy in Southwest Asia during the Late Chalcolithic period from 4500 to 3800 BC. Artefacts from this period include eight massive gold rings weighing a total of almost 1 kg (2.2 lb.) from the Nahal Qanah Cave, Israel, and prestige copper items from a cave at Nahal Mishmar near the Dead Sea, which display lost wax casting technology.

However, the origins of this metalworking tradition have remained obscure until recently. Now a newly-published report has suggested that the roots of southern Levantine metallurgy might be found in an earlier, non-local tradition. Tel Tsaf in the Jordan Valley was excavated between 2004 and 2007. The main period of occupation of the site occurred during the Middle Chalcolithic, and dates to between 5100 and 4600 BC. The mud-brick complex included courtyard buildings and grain silos, two of which had been repurposed as graves. Artefacts from the site included elaborately painted pottery and over 2,500 beads made of ostrich egg-shells and stone. Many artefacts were of non-local origin, including obsidian items from Anatolia or Armenia, a shell from the Nile and pottery from northern Syria or Mesopotamia. Animal remains included large numbers of cattle and pigs and the capacity of the grain silos has been estimated at around 15 to 30 tons. Wealth and food surpluses were being accumulated at Tel Tsaf far in excess of anything else known in the region during this period; and the site had access to long-distance exchange networks throughout Southwest Asia.

From one of the silo-graves was recovered a badly-corroded copper awl. The awl is a 41 mm (1.6 inch) pin made from cast copper, with a rounded cross-section. The maximum diameter is 5 mm (0.2 inch), narrowing to 1 mm (0.04 inch) near the tip. The burial held the remains of a woman aged around forty, and other grave goods included an ostrich-shell bead necklace with 1,668 beads.

Chemical analysis indicated the metal composition of the awl included 6 percent tin and 0.8 percent. Although corrosion may have altered the chemical composition of the awl, the presence of tin suggests that it was not of local origin. Copper items of such a composition have not been found in the Late Chalcolithic or the Early Bronze Age of the southern Levant, nor does it match the composition of local native copper. It is thought that the alloy is natural, as it unlikely that artificial copper/tin alloys were being produced at this stage. Tin bronze is not known from the region until the Middle Bronze Age, around the second millennium BC. Thus the awl not only predates all previously-known metal artefacts in the southern Levant by several centuries, it also predates all known tin bronze items in the region by around 3,000 years.

Assuming that the awl is not of local origin, then it must have reached Tel Tsaf via long-distance exchange networks. Metallurgy must have diffused to the southern Levant from the north. At first, artefacts were imported and it was not until some centuries later that they were produced locally. Thus it can be seen that the elaborate Late Chalcolithic metallurgy of the southern Levant developed from an earlier, non-local tradition.

That the awl was found in an elaborate grave suggests that at this stage, metal items were seen as rare and prestigious. The residents of the courtyard building where the grave was found apparently belonged to a family or group that controlled the local cultivation and storage of grain as well as long-distance trade. Their wealth may have either led to or been the result of a trade in luxury items obtained from sources very remote from Tel Tsaf.


1.  Garfinkel, Y., Klimscha, F., Shalev, S. & Rosenberg, D., The Beginning of Metallurgy in the Southern Levant: A Late 6th Millennium CalBC Copper Awl from Tel Tsaf, Israel. PLoS One 9 (3), e92591 (2014).x

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