Age of iron    

Pure copper was found in nature as early as the Stone Age, and knives and chisels repeating forms of stone objects were manufactured of it by beating. The oldest metal tool in Finland so far is a copper groove chisel, which goes back to the end of the Stone Age (Huurre 1986). The object has been influenced by the early metal culture of Eastern Europe, which had a strong effect on Inner and Northern Finland for two or three millennia. Later, people learnt to mix up copper and 10 % of tin, which together formed bronze, a firmer metal than before.

In the early Metal Age (about 1900/1500 BC–AD300) especially from the Volga–Oka area, finished bronze and iron objects as well as knowledge on manufacture technology of metal objects were brought to Finland along old trade connections (Carpelan 1999). In Lapland, the curved iron daggers of the ancient Sillankorva dwelling place in Kuosku, Savukoski foreshowed the beginning of independent iron manufacture (Erä-Esko 1969). These daggers, which obviously date from the 5th century BC, were brought from Eastern Russia, from the area of the Ananino culture by the lower course of the River Kama (Carpelan 2003). 

Learning to work with bronze

Bronze articles were often cast in moulds made of steatite or clay. The desired form could be obtained by using wax running out of the mould while being burnt. Its use is probably referred to by the spouted jugs or melting pots modelled of coarse clay substance found in Neitilä, Kemijärvi and Kiikarusniemi, Sotkamo (see Huurre 1986, Kotivuori 1997). These vessels could be trainoil lamps, too. Remnants of a footed, goblet-like vessel are also known from the above-mentioned places as well as from a dwelling place in Varaslampi, Joensuu. More typical of the Early Metal Age are often types of ceramics mixed with asbestos, talc or mica (Lovozero, textile, imitated textile and Anttila ceramics). Kjelmøy ceramics that was in use at the turn of the Christian Era, about 700 BC–AD300, is quite common in the northern dwelling and iron manufacture places (see Carpelan 2003). Pieces of iron have even been mixed with ceramic clay (Willemark 1989). That is why Kjelmøy ceramics has been presumed to be directly related to iron manufacture, but in practice vessels do not endure heat of over 1100 °C, which is needed for melting iron (cf. Hulthén 1991, Baudou 1995). In that case, finishing decoration of a vessel surface would also be unnecessary.

Slabstone furnaces

The two iron manufacture places I researched in Riitakanranta and Maununiemi in Sierijärvi, Rovaniemi during the years 1989–1991 contained pieces of at least thirteen Kjelmøy vessels (Kotivuori 1996). According to carbon deposit datings, the pieces from Kotijänkä, Maununiemi are older than iron manufacture, from about the 700’s–400’s BC. On the basis of a calibrated radiocarbon dating (Hel-3173) 1880 ±110, the smelting furnace constructed of stoneslabs in an earth pit goes back to about 10 BC–AD 260 or AD 300–320. One calibrated radiocarbon dating (Hel-2955, 2090±100) of a slabstone furnace researched in Riitakanranta goes back to about 360–310 BC or 320 BC–AD 20. As to another dating of the furnace (Hel-2965, 1820±110), it corresponds, when calibrated, the age of about AD 70–340. The large dispersion of datings proves that iron has been manufactured for domestic needs at about the turn of the Christian Era. 

In Finland, iron manufacture places of the Early Metal Age have been researched in the dwelling places of Neitilä in Kemijärvi, Äkälänniemi in Kajaani and Kitulansuo in Ristiina (Kehusmaa 1972, Schulz 1986, Lavento 1999). Datings (Hel-2098, 2220 ±100 and Hel-2101, 2180 ±90), which according to a calibrated result go back to about 400–120 BC, have been got from the Äkälänniemi find, which structurally corresponds to the furnaces of Sierijärvi. Many corresponding rectangular slabstone furnaces have been researched in Eastern Karelia, among others seven remnants of furnaces in a dwelling place called Kudoma XI in Säämäjärvi (Kosmenko & Manuhin 1999). However, according to radiocarbon datings they are younger than their Lappish equivalents, from about AD 400–1300, like the slabstone furnace of Kitulansuo, Ristiina (Lavento 1999). This type of furnace seems to have been in use from the end of the Early Metal Age to the Middle Ages. Chronologically, the datings of these furnaces do not confirm the assumption that innovation would have come from the east or north-east. However, several early iron manufacture places, the datings of which are questionable, but which on the basis of other find material refer to the time before the Christian Era, are known from Eastern Karelia (see Kotivuori 1996, Kosmenko & Manjuhin 1999). In spite of the dating results, part of the Kjelmøy ceramics and a possibly local-made iron knife from the dwelling place of Kotijänkä in Sierijärvi, Rovaniemi may be iron smelters’ equipment. In the first place, knives, possibly arrowheads and axes with wooden handles inside them, too, have been made of iron.

Ideas of the smelting results

On the basis of their structures and ways of working, iron smelting furnaces can be divided into many different types, the uses of which contain regional and cultural characteristics. The most primitive forms are usually represented by different pit smelting places and a more developed way of manufacture by so-called shaft furnaces (e.g. Mäkivuoti 1988). The volume of the Kotijänkä furnace was about 50 litres, as its area was about 40 x 50 cm and height about 25 cm. The furnaces from Kajaani and Ristiina were also about the same size. On the basis of the volume, it can be estimated that about 8–10 kilograms of ferrous bog or lake ore (hölmä or limonite), which had been dried by burning (roasting), were needed for one smelting process, which produced 1,5–2,0 kilos of workable iron (Kotivuori 1996). During a smelting process, charcoal or chopped firewood were first burnt in a furnace, and ore was added in the end. Slag was let to run out through a furnace hole. The ore heated by means of bellows melted, and finally formed an iron cake on the bottom of the furnace.

Hannu Kotivuori, The Provincial Museum of Lapland
www.rovaniemi.fi/maakuntamuseo

 References

  • Baudou, E. 1995. Norrlands forntid – ett historisk perspektiv.
  • Carpelan, C. 1999. Käännekohtia Suomen esihistoriassa aikavälillä 5100…1000 eKr. Pohjan poluilla. Suomalaisten juuret nykytutkimuksen valossa. Bidrag till kännedom av Finlands natur och folk 153.
  • Carpelan, C. 2003. Inarilaisten arkeologiset vaiheet. Inari–Aanaar. Inarin historia jääkaudesta nykypäivään (toim. Veli-Pekka Lehtola). Oulu.
  • Erä-Esko, A. 1969. Akinakeslöytö Pohjois-Suomesta. Suomen Museo 1969.
  • Hulthén, B. 1991. On Ceramic Ware in Northern Scandinavia during the Neolithic, Bronze and Early Iron Age. Archaeology and Environment 8.
  • Huurre, M. 1986. Esihistoria. Kainuun historia I. Kajaani.
  • Kehusmaa, A. 1972, Neitilä 4. Pro gradu -tutkielma Suomen ja Skandinavian laudatur-arvosanaa varten. Helsingin yliopiston arkeologian laitos. Moniste n:o 3.
  • Kosmenko, M. G. & Manjuhin, I. S. 1999. Ancient iron production in Karelia. Fennoscandia archaeological XVI.
  • Kotivuori, H. 1996. Pyytäjistä kaskenraivaajiksi. Rovaniemen asutus noin 6000 eKr.–1300 jKr. Teoksessa: Veikko Kallio (toim.), Rovaniemen historia vuoteen 1721.
  • Kotivuori, H. 1997. Poimintoja Kemijärven Neitilän tulvalietteestä. Raito 2/1997.
  • Lavento, M. 1999. An iron furnace from the Early Metal Period at Kitulansuo in Ristiina, in the southern part of the Lake Saimaa Water System. Fennoscandia archaeolociga XVI.
  • Mäkivuoti, M. 1988. Esi- ja varhaishistoriallinen raudanvalmistus Pohjois-Suomessa. Sivuainelaudatur-tutkielma. Suomalainen ja vertaileva arkeologia. Turun yliopisto.
  • Schulz, E.-L. 1986. Ein Eisenverhüttungsplatz aus der älteren Eisenzeit in Kajaani. Iskos 6.
  • Sundqvist, Ø. 1999. Traces of iron in prehistoric Finnmark. Fennoscandia archaeological XVI.
  • Willemark, K. 1989. Ödinge, en uppehållsplats genom förhistorien. Arkeologi, fjäll, skog och bygd. 1. Stenålder – tidig järnålder. Uddevalla.