Examination of the Baltic amber inclusion surface using SEM techniques and X-ray microanalysis

Abstract

Amber inclusion of the leafhopper, partly revealed from the resin and covered with inorganic, blackish and shining layer was examined using light and scanning electron microscopes. It is placed in the genus Protodikraneura of the recently described tribe Protodikraneurini (Insecta: Hemiptera: Cicadellidae: Typhlocybinae). SEM examination was conducted using microscope Hitachi S-3400N, equipped with X-ray EDS spectrometer of Thermo Noran Company, suitable for local chemical analyses. Part of the tegmen of the inclusion with details of its morphology is visible both in light and SEM microscopy. Its detailed structure and composition remained unidentified under light microscopy. Surface morphology and the chemical composition of the layer covering inclusion in particular, were studied in details using SEM microscope with the EDS X-ray spectrometer. The layer covering revealed portion of the inclusion presented various surface structures and various topographic features. The structure (grains of different shapes and sizes) is diversified in respect to their chemical composition. Qualitative and quantitative EDS analyses as well as the structure of grains building fragment of the layer were conducted. The surface of inclusion is partly covered with pyrite FeS 2, probably with one of the variations of the pyrite — the marcasite. Other portions of the surface layer differ in chemical composition and in physical structure of the grains, containing high amount of aluminum and silicon.