Tzankova N. 2017. Analysis of beads from feature 73A.- In: Sarnevo. Pits from the Late Neolithic, the Early and Late Iron Age, and the Roman Period. Volume 1. The Late Neolithic pit field, National Institute of Archaeology and Museum – BAS, Edited by K. Bacvarov, M. Tonkova, and G. Katsarov, 565-570 (in Bulgarian with English abstract).
The mineral composition and gemological properties of four mineral beads have been analyzed out of a total of 47 beads deposited in feature 73A. A nondestructive approach was adopted with the use of gemological microscope, polariscope with conoscope, dichroscope, specific gravity kit, magnet, and XRD analyses. The mineral artifacts were made from showcase good knowledge about and deliberate use of specific raw materials: copper ore (malachite and azurite) and serpentinite (ultrabasite). The four beads measure ca. 3 mm in diameter and less than 1 mm in thickness. A piercing tool was used to make the holes. Their perfect workmanship sheds light on the well-developed skills of the ancient masters and on the techniques they used: grinding, giving the bead a rounded convex shape, polishing, piercing of a round hole, and possible use of a holder, which provided precise positioning.
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