Copper Mines of Bronze Age in Southern Trans-Urals (original) (raw)

The paper presents data on the Southern Trans-Urals copper mines, developed in the Bronze Age: Vorovkaya Yama, Novonikolaevsky and Novotemirsky. The geodynamic positions of this copper mines are reviewed. The results of field work on ancient mines are described, including the compilation of large-scale geological schemes and sections of ancient excavations, partial overburden mining, and the search for tools of ancient mining. Laboratory researches of ores and ancient metallurgical slags mineralogy were carried out by optical and electron microscopy, formulas of minerals and some petrochemical coefficients were calculated. Copper ores are confined to ultrabasites and granitoid intrusions. The ores found in the settlements are represented by four main types: malachite-azurite, malachite-magnetite, malachite streaky-impregnation, and tourmaline-malachite. Mineralogy of copper ores is represented by malachite, azurite and accessory minerals: chalcopyrite, bornite, chrome spinels, cobaltite, cobaltpentlandite, mauherite, chrysocolla, iodargyrite. The conducted geophysical surveys made it possible to establish that the primary depth of the quarries differed from the present108 day surface by 1–2 m. Research of ancient mining objects, combined with geophysical methods, allows more accurate determination of mine development technology and the volume of useful component extraction. The age of the mines is determined from the finds of the Bronze Age and Early Iron Age ceramics and the radiocarbon dating of the coal particles found in the dumps. The sections of the mine dumps indicate several stages of the ancient mines development, which is confirmed by the horizons of buried soils. Fragments of metallurgical slags were found at the Vorovskaya Yama mine, similar to those found in the neighboring settlements of the Zingeika archeological microdistrict, referring to the Sintashta and the SrubnoAlakul cultural-historical stage. Findings of ceramics related to different cultural and historical periods, comparison of metallurgical slags with analogues in the settlements of the Early and Late Bronze Age, as well as radiocarbon dating of coal from dumps, allow us to conclude that the Southern Trans-Urals mines were used for a long period in ancient times.