Kodumanal's Bead Workshops, Iron Furnaces and Steel Crucibles on the Noyyal River Have Five Radiocarbon Dates, Measured at Beta Analytic and the University of Arizona, Running From About 480 BCE to 200 BCE

Kodumanal, a village on the north bank of the Noyyal river in Erode district, western Tamil Nadu, was once a town of bead cutters, ironsmiths and steelmakers, and the excavators now have radiocarbon dates for it. K. Rajan of Pondicherry University published five of them in a lecture for the Archaeological Survey of India on 25 August 2014. Three were measured by Beta Analytic in Florida and two by the accelerator mass spectrometry laboratory at the University of Arizona. Calibrated into calendar years, his figures run from 480 BCE for the deepest sample to 200 BCE for the shallowest.

The deposit those samples came from holds the bead workshops, an iron smelting furnace, a crucible furnace and more than 500 pot fragments inscribed in Tamil-Brahmi, the early script of the Tamil country. This article sets out who dug the site, who dated what and by which method. For the other well-known Tamil-Brahmi site, see our piece on Keezhadi, which has its own radiocarbon story and is not retold here.

A village on a trade road

Kodumanal lies in Perundurai taluk, and The News Minute puts it 41 km south-west of Erode and 26 km east of Tiruppur. The report on the site’s skeletal remains, written by S. R. Walimbe, Rajan and colleagues, places it on the ancient route that joined Karur, the Chera capital of the Sangam age, to the west-coast port of Muziris through the Palghat gap. Our article on Muziris and the Pattanam digs covers the port end of that road.

The same report records that the Sangam anthology Patirruppattu names the place Kodumanam in its poems 67 and 74 and describes it as a bead-making centre, and a 2025 paper in the International Journal of Informative and Futuristic Research repeats the identification. The excavators match the site to that name from the trade route, the crafts and the personal names on the pottery. The radiocarbon dates do not test the match. Our overview of Sangam literature explains the anthologies.

The digging has gone on for six decades. V. N. Srinivasa Desikar of the Archaeological Survey of India first reported the site in 1961, The News Minute and Business Standard both say. Tamil University, Thanjavur, dug in 1985, 1986, 1989 and 1990 under Y. Subbarayalu and Rajan, with Madras University and the state archaeology department, and the state department re-excavated in the late 1990s. Pondicherry University, under Rajan, dug from April to June 2012. In a 2014 count Rajan put the work at seven seasons, with 61 trenches in the habitation and 17 burials opened. The state department returned for 2019 to 2020 and 2020 to 2021, The News Minute reports.

Five measurements, two laboratories

A radiocarbon age is counted in years before present, with 1950 as the zero point, and calibration turns it into calendar years. Rajan’s table lists, for each sample, the laboratory number, the depth below the surface, the measured age, the uncalibrated date and the calibrated date. The two-sigma range, which carries roughly a 95 percent probability, comes from the laboratories. From the shallowest sample to the deepest:

• 15 cm, Beta-351053: 2150 plus or minus 30 years before present, calibrated at 200 BCE, with a two-sigma range of 350 to 110 BCE in three segments.
• 60 cm, University of Arizona AA99856: 2225 plus or minus 41, calibrated at 380 BCE, range 389 to 199 BCE.
• 65 cm, Beta-349958: 2250 plus or minus 30, calibrated at 370 BCE, range 390 to 210 BCE in two segments.
• 80 cm, Beta-330303: 2280 plus or minus 30, calibrated at 380 BCE, range 400 to 230 BCE in two segments. The table gives the depth as 80 cm and the lecture’s text as 85 cm.
• 120 cm, University of Arizona AA99855: 2358 plus or minus 40, calibrated at 480 BCE, range 731 to 368 BCE in three segments.

The lecture titles the table as dates for samples associated with Tamil-Brahmi inscribed potsherds and does not say what material was measured. The lecture reads the set as a range of 200 to 408 BCE, uncalibrated, for the deposit between 15 and 120 cm. On the strength of the dates Rajan re-labels the whole habitation deposit Early Historic, the term archaeologists use for the age of writing, coins and long-distance trade that follows the Iron Age, though the lecture notes that they do not all define it the same way.

An iron furnace on the edge of town

The excavators found iron-making in two places about 300 m apart. On the southern edge of the habitation mound, a resistivity survey over a scatter of slag covering about 100 square metres suggested a cluster of furnaces. One of three trenches there exposed the circular base of a furnace 115 cm across, sitting at a depth of 65 cm directly on the natural soil.

Around it lay iron slag, burnt clay stuck with slag, vitrified brick pieces and a granite slab that the report suggests was used for forging. The clay air pipes, called tuyeres, were 15 cm long and 6 cm thick with a 1.5 cm bore, which the report reads as a sign that the bellows worked close to the furnace. The state department’s 2025 volume on iron dates says the furnace probably reached 1,300 degrees Celsius, high enough to reduce the ore to iron but below the temperature at which iron melts, and that smelting was done in the open on the fringe of the settlement. Iron ore sources lie around Chennimalai hill, about 15 km to the east, and both the report and Business Standard tie the town’s ore to them.

A crucible furnace for steel

Fifteen trenches about 300 m north of the smelting area produced two crucible furnaces, one of them unused. The main furnace was oval, about 112 cm by 100 cm and 40 cm deep, with a clay wall 20 cm thick, and was ringed by more than twelve small furnaces about 30 cm across at the mouth. In one small furnace the excavators found a broken bowl-shaped crucible 9 cm across the mouth, its surface glazed by heat, still in place. All of it lay at the bottom of the deposit, at 125 cm.

Steel here means iron carrying between 0.15 and 2 percent carbon, as the 2025 state volume defines it, and crucible steel, also called wootz, is made in small clay crucibles by adding carbon to wrought iron. Rajan’s 2014 lecture cites analyses of the Kodumanal material by Sasisekaran in 2004 as suggesting that steel was produced. Business Standard reported in 2012 that Rajan said Sharada Srinivasan of the Indian Institute of Science had examined the crucible and confirmed the find. Srinivasan’s 2007 paper in the Indian Journal of History of Science covers Kodumanal alongside Mel-siruvalur and Pattinam, and the 2025 volume cites it among the best examples of crucible steel in Tamil Nadu. Our article on wootz and Damascus steel tells the wider story.

The crucible furnace has two published dates. The 2014 lecture ties it to the 5th century BCE, and the 125 cm furnace lies 5 cm below the deepest radiocarbon sample at 120 cm. The 2025 volume says it was firmly dated to the 6th century BCE and cites Rajan’s 2016 paper, which this article could not open.

Beads in every stage of making

The Walimbe report lists beads of sapphire, beryl, agate, carnelian, amethyst, lapis lazuli, jasper, garnet, soapstone and quartz from the habitation. It says finished and half-finished beads, drilled and undrilled, polished and unpolished, turned up with raw stone, discarded chips and a grooved stone slab with a few grooved beads still in it, and reads that as local manufacture.

Some raw stone was close at hand. The same report puts the beryl site of Padiyur about 15 km south, sapphire hills about 15 km south-east, and quartz mounds about 5 km north and south. Carnelian and lapis lazuli do not occur near Kodumanal. The report suggests carnelian came from Gujarat and Maharashtra and lapis lazuli from Afghanistan, and The News Minute says carnelian occurs naturally in Gujarat only.

The graves hold the largest counts. The report records about 80 carnelian beads in one burial, about 1,000 in another and about 2,220 in a third, and adds that 2,220 in a single burial may be the first such find in India. The Chennai Government Museum’s 2011 report describes a cairn circle at Kodumanal whose urn held 782 carnelian beads.

Writing, cloth and names

The report counts more than 100 Tamil-Brahmi potsherds from the earlier digs, and Rajan’s 2014 lecture puts the total above 500. Business Standard reported that the 2012 season found 130 inscribed sherds in four trenches, against 170 from 49 trenches in 1985 to 1990. The report names Kannan and Sattantai among the personal names, and Business Standard reported that nearly all the 2012 inscriptions are personal names, a few of which also name a trade. Rajan’s lecture and Business Standard both note Prakrit words, which he reads as contact with the north.

The excavators also recovered terracotta spindle whorls pierced with an iron rod and a piece of woven cotton, which they take as evidence of a weaving industry.

What the dates cover and what they leave open

The five dates cover the deposit between 15 and 120 cm. The topmost 15 cm and the lowest part of the deposit have no published radiocarbon date. Rajan gives the total deposit as 185 cm, so 65 cm of layers with inscribed pots lies below the deepest sample. He calls it hypothetical, but assumes two years of accumulation for each centimetre, which adds about 130 years and takes the base to the middle of the 6th century BCE. That figure is his extrapolation. The lecture presents no measurement for it.

The excavators’ own statements on the site’s span differ with the date of writing. The earlier excavation report divided the deposit into a megalithic period dated 400 BCE to 100 CE and an Early Historic period dated 100 to 300 CE, then noted that Rajan had revised the start to the 4th century BCE on the evidence of the inscribed pottery. Business Standard quoted Rajan in 2012 as calling the site a manufacturing and trading centre in the 4th century BCE, abandoned after the 3rd century CE. The News Minute quotes him as giving 480 BCE to the 1st century BCE from carbon dating. A 2018 review by Jenee Peter in the journal Heritage says dates from Kodumanal and other southern sites have moved the start of the Early Historic period there to the 5th century BCE.

The 2019 to 2021 state seasons are reported so far only in the press. The News Minute says they found an iron-working zone with slag and furnaces on a larger scale than earlier seasons, and a step well, and that J. Ranjith was project director. The department’s report on those seasons was not among the sources opened for this article. As of 2 November 2026 the five measurements above are the only Kodumanal radiocarbon dates found in the published sources opened for it.