Vanishing iron-smelting furnaces of the South Eastern Altai, Russia – Evidences for highly developed metallurgical production of ancient nomads

Abstract

Abstracts Results of multidisciplinary investigations of ferrous metallurgy archaeological sites within four locations in the South Eastern Altai, Russia are presented. Radiocarbon dating applying both conventional and AMS techniques evidences for constructing and operating of iron-smelting furnaces during the Turk period: the second half of the 5th-11th centuries AD. Trees (Larix Sibirica) more than 100 years old were utilized for charcoal production. Generally, larches, growth in 2nd-10th centuries AD, were used in metallurgical process in the Kuektanar-1, Kuektanar-2, and Turgun-1 sites belonging to the Chuya-Kurai metallurgical zone. The time of the last iron production for the bloomery iron-smelting furnace in the Kuektanar-1 site was reliably established falling between AD 655 and 765. Mineral composition of slag from the Kuektanar-1 site indicates that two types of the ore - quartz-hematite and siderite, could be utilized for iron production. The high Ca, K and Al content in some slag droplets evidence for possible presence of calcite in the initial ore, or flux additives. A small amount of fluxes could come from the clay lining of the bloomery hearth. Generally, high concentration of furnaces near the Kuektanar mouth and in the Turgun valley was determined by wide spreading of forest vegetation in an area and close location of ore occurrences. Intensive timber consumption by nomadic societies together with the progressive aridity intensification led to total deforestation of the eastern part of the Chuya depression.