VOLUME 48 (2)/August 2019

The most representative subsurface section of the Famennian carbonate succession from the Moesian Platform in Bulgaria occurs in the R-2 Preslavtsi well. Nine microfacies types (MFTs 1–9) have been distinguished and described in the intraclastic and peloidal limestone unit and the organogenic limestone unit. They are grouped in four microfacies associations: 1) protected shallow subtidal (lagoon) (MFT 1, bioclastic-peloidal packstone/grainstone; and MFT 2, oncoidal wackestone); 2) wave-dominated shallow subtidal (MFT 3, intraclastic-peloidal grainstone and rudstone; MFT 4, oncoidal rudstone; MFT 5, peloidal-bioclastic packstone and grainstone); 3) reef (MFT 6, solenoporacean-calcimicrobial-stromatoporoid boundstone; MFT 7, crinoid-stromatoporoid floatstone); and 4) open-marine (MFT 8, bioclastic wackestone/packstone with intraclasts and peloids; and MFT 9, bioclastic wackestone and packstone). The carbonate deposits are interpreted as formed in various shallow- to open-marine environments at or above the fair-weather wave base (MFTs 1–7) and below it (MFTs 8 and 9). Most of the described microfacies are comparable with Wilson’s (1975) Standard Microfacies Types.

The glass beads from the Dren-Delyan necropolis are found in burial complexes dated as from the end of the 6^th century BC until the first half of the 4^th 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.