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 a 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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