The results of studying the composition of glasses from the site of the Zhabinsky factory, one of the first Russian glass factories founded in the north-west of Russia, are presented. More than 200 samples of historical glass fragments of dishes, as well as the remains of glass on the walls of melting pots were studied using X-ray fluorescence analysis. The data obtained made it possible to classify glasses depending on the recipe and the raw materials used in their production. The reliability of the determination of the compositions was confirmed on randomly selected samples by the ICP AES method. The presence of cobalt impurities was qualitatively determined from the characteristic bands in the absorption spectra of the visible region. The main group of finds is represented by potash-calcium glass obtained using plant ash (ash glass) or purified potash (potash glass). A separate group includes potash-lime glasses obtained through addition of lime to the batch. The nature of the coloration of the studied glasses with iron (+2), iron (+3), cobalt (+2), and also due to the charge transfer iron (+3) — sulfur (–2) is discussed. Potassium-lead glasses with a high lead content found at the site of the plant serve as an example of the first Russian colorless lead crystal. The results represent the first systematic study of the composition of glass produced in Russia in the time of Peter the Great. A comparative analysis of the compositions of glasses from the Zhabinsky and Lavinsky factories has been carried out.
A method for the determination of the glass composition in the systems PbO – SiO2 and K2O – PbO – SiO2 with different additives present both in historical and modern art glass is considered. Development of a non-destructive method for determining the glass composition in conditions of museum storage is an important goal for museum practice. We propose a method for determining the composition of those glasses using a portable X-ray fluorescence analyzer (XRF). To select the optimal software suitable for measurements, we have synthesized a number of standard glass samples with the composition determined by ICP-AES. A glass sample of was dissolved in an autoclave in a mixture of nitric, hydrofluoric, and perchloric acids. The lead content in standard samples was simultaneously determined gravimetrically after fusion of the sample with sodium carbonate. Using XRF measurements of standard samples we development of a method for determination of the glass composition with an accuracy sufficient to assign the glass to one of the groups of historical glasses. The results obtained can be used for attribution of lead glass products. The content of potassium oxide in historical samples was estimated by XRF method using two independent programs with subsequent averaging of the data obtained. When using our method, the error of potassium, silicon and lead determination does not exceed 10%, which is sufficient for a museum description and attribution of an item. The developed procedure was tested in analysis of the items from the collection of the State Museum of Ceramics («Kuskovo Estate of the 18th century»).
Compositions of Russian glasses of the 18th century manufactured at state-own factories have almost not been investigated so far. This work presents the results of studies of the composition of glasses found in 2020 on the place of Lava Factories (1730–1760th). The composition of glasses was determined using complementary analytical methods: X-ray fluorescence spectrometry, energy-dispersive X-ray electron probe microanalysis, and optical spectroscopy. The general type of glasses (K 2 O–CaO–SiO 2 ) was revealed and also groups of glasses corresponding to various melting formulations were distinguished. The role of various functional additives to the studied glasses is discussed.
The dependence of lead silicate glass color, applied using copper(ii) ions, on lead content in the glass, the nature of the alkali metal, and copper content was studied. It was shown that the principal contribution to the color is made by the shift of the fundamental absorption edge, which correlates with the amount of lead and copper ions. According to EPR results for glasses with the studied compositions, copper ions have a tetragonally distorted octahedral coordination environment, which does not change considerably with composition. The Cuii d—d-transition bands also do not undergo considerable changes.