Chemical characterization of glass beads from the necropolis of Dren-Delyan (6th–4th century BC), Southwest Bulgaria

Article in Press
Pages: 
pp. 31-50
University of Mining and Geology “St Ivan Rilski”, Department of Mineralogy and Petrography, 1700 Sofia, Bulgaria
Regional Historical Museum – Pernik, 2 Fizkulturna Str., 2300 Pernik, Bulgaria
Abstract: 

The glass beads from the Dren-Delyan necropolis are found in burial complexes dated as from the end of the 6th century BC until the first half of the 4th century BC. The purpose of this study is to obtain data on the chemical composition of the glass and the technology of its production. LA-ICP-MS and SEM-EDS analyses were conducted.
   The analysed glass beads are classified as a low-magnesium type (LMG), and only one of the samples is determined as high-magnesium glass (HMG). The yellow colour of the glass is due to crystals of lead antimonate incorporated into the glass matrix. The green colour of the beads is a result of interaction of added copper and lead in the glass mixture, in presence of iron and chromium. Dark blue samples are coloured by additives with cobalt, copper and lower iron content. Light blue colouration of opaque glass beads is due to high copper content, along with the presence of iron. The colouring agent of a transparent light blue bead is FeO in amount up to 0.25 wt%. The brown colour is associated with high iron content. Two different opacifiers were used for the production of opaque glass beads – antimony and tin, either individually or together. The decolourising agent is antimony without the involvement of manganese. Based on the results of the studied glass beads, we assume at least four types of raw material mixtures for their production. Comparison of the obtained results and published data about similar ancient glass findings was made.

Keywords: 

glass beads, LA-ICP-MS, SEM-EDS, archaeology, 6th–4th century BC

VOLUME 48 (2)/August 2019

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria
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University of Mining and Geology, Department of Hydrogeology and Engineering Geology, Studentski Grad,Prof. Boyan Kamenov Str., 1700 Sofia, Bulgaria
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Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 24, 1113 Sofia, Bulgaria

University of Mining and Geology “St Ivan Rilski”, Department of Mineralogy and Petrography, 1700 Sofia, Bulgaria
|
Regional Historical Museum – Pernik, 2 Fizkulturna Str., 2300 Pernik, Bulgaria