The Metallurgy of Norse Material from L’Anse aux Meadows, Newfoundland

This study deals with the investigation of 155 samples of ferrous material, slag, ore and clay, as well as two copper alloy artifacts, all excavated at the Norse archaeological site of L'Anse aux Meadows, Newfoundland. This is the only Viking and the oldest European settlement discovered so far in North America. The most important aims of this metallurgical examination were to identify and characterize the archaeological material, determine its composition and structure, and ascertain the methods of manufacture of the artifacts as well as the technological processes applied in their production. The study was done to determine if the artifacts were in fact of the same origin as the site and if they were produced by people living there in the early historic period, thus giving further evidence for pre-Columbian Norse exploration of the area. The investigation was carried out using classical and modern metallographic and analytical techniques including optical microscopy under reflected and transmitted polarized light, scanning electron microscopy, hardness testing and microhardness measurements, radiography, energy dispersive X-ray fluorescence, atomic absorption spectroscopy, X-ray diffraction and other techniques.

Metallurgical examination enabled us to distinguish five different types of iron working residues at L'Anse aux Meadows, i.e. smelting slag, smithing residues, cinder, bear or slagged furnace lining, and silicious refractory. The melting temperature of the smelting slags, estimated to be 1150 to 1200°C, falls within the normal working range of the bloomery iron production process. Comparison of the L'Anse aux Meadows slag material with a large number of old bloomery European slags from different historical periods showed great similarity in external appearance, physical properties, chemical composition, structure, constitution and melting temperature. […]

There is no doubt that iron working was carried out at L'Anse aux Meadows as remains of a smelting furnace and the two most important raw materials, rich iron ore and fuel, as well as bloomery slag and bloomery iron artifacts were found at the site. Evidence of fuel is shown by the charcoal kiln, many charcoal pieces found in the settlement and even some embedded in the slag. Matching the ores from L'Anse aux Meadows with the slags linked the slags directly to the area of the site. Some of these slags were proven to be smithing slags and hammer scale indicating that, in addition to smelting, also smithing operations were carried out at the site.[…]