Abstract
During the exploitation of the Zakhidne Pershe amber deposit in the Klesivskyi amber-bearing district, black organic material classified as “black resins” was found among the extracted amber (succinite) in the sediments of the productive Mezhyhirska suite of the Oligocene division of the Paleogene period in the interval of 6.6–9.0 m.The samples were taken on the conveyor of the enrichment plant during the enrichment of amber-bearing rocks extracted from the open-pit wall. To date, 15 samples of various shapes and weights have been found. All specimens are dark brown or black, have a shell-like fracture, and weigh between 20 and 250 g.Among the found samples of fossilized resinous material, five specimens were submitted for further identification. The gemological characteristics were determined and the samples were analyzed by FTIR spectroscopy. The totality of the data obtained indicates that the material submitted for examination can be diagnosed as a stantienite–pseudostantienite.Stantienite is known to be found in Ukraine at the Klesivskyi amber deposit and the Volodymyrets Skhidnyi amber deposits. Several samples of stantienite from the Klesivskyi amber deposit are in the collection of black fossil resins of the PAN Earth Museum. However, there are currently no officially documented and described finds of such “black resins” on the territory of Ukraine, and an important task is to determine not only their physical and chemical properties, but also their source. The study of fossil resin varieties makes it possible to expand the existing knowledge about the paleogeographic and paleoclimatic conditions that prevailed in Polissya in the Paleogene, and for paleobotany it will help to clarify the distribution areas of different types of resin-producing vegetation.The research was conducted within the framework of a scientific project between the Polish Academy of Sciences and the National Academy of Sciences of Ukraine “Amber – a natural and cultural phenomenon of Poland and Ukraine” 2025–2027.