Applications of EPMA and SEM-EDS

This study is focused on Roman lead-glazed inkwells from the archaeological site of the “Nuovo Mercato di Testaccio” (Rome, Italy) dated in the half 2nd century AD. Optical microscopy (OM), X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and electron microprobe analysis (EMPA) have been used. Petrographic analysis of the body indicated the occurrence of only one fabric. The reaction zone at the contact glaze/body is marked by the enucleating of euhedral Pb-bearing alkali feldspar from a felsic melt enriched in Pb as revealed by EMP analysis. The mineralogical assemblages of the body and glaze, the microstructure and the chemical composition suggest that the inkwells were fired in the range 950–1100 °C, under oxidizing conditions.

The world-class coal-hosted Ge ore deposits of Wulantuga (Inner Mongolia) and Lincang (Yunnan Province) in China display unusually high concentrations of some trace elements, including Be, Ge, As, Sb, Nb, W, and U. In coal, these elements may be associated with the macerals and/or with the inorganic fraction (e.g., minerals and amorphous phases). Distinguishing among different associations is important for practical applications, but still challenging. In this study, an in situ electron probe micro-analysis (EPMA) technique was applied in order to map the distribution of both light elements (C, O, and S) and selected trace elements (Wulantuga: Ge, W, and As; Lincang: Ge, W, As, and U) in the high-Ge lignite samples and their low-temperature ashes (LTAs). The EPMA detection limit was stable for these light and trace elements commonly associated with organic matter, so that reliable point analysis data were acquired for individual macerals. Additional mineralogical and geochemical data were obtained by petrographic microscopy, XRD, EDS, and ICP-MS analyses. WDS in situ element mapping and point analysis demonstrate that the huminite in the Wulantuga coal has a lower C content and higher O and S contents relative to inertinite, and Ge, As, and W show a preferential enrichment in huminite. Among the different huminite macerals in both the Wulantuga and Lincang coals, Ge, As, W, and U tend to occur in more compact huminites (ulminite or gelinite), and their abundances show mild to considerable variations across the compact huminites. The in situ concentrations of Ge and W display a direct correlation, suggesting their co-affiliation with organic matter. Elements such as Ge, W, and U have a considerable organic affinity, with a minor fraction associated with inorganic S-rich phases, such as iron sulfide/sulfate (e.g., pyrite and copiapite). Arsenic has a mixed affinity to organic matter and iron sulfide/sulfate. No Ge minerals have been detected in the LTAs, and Ge in the LTAs is likely to exist in an inorganically amorphous state. This study could provide new perspectives on the modes of occurrence of trace elements concerned in the coal-hosted germanium ore deposits in China.

BSEM/EDS Archaeometallurgy Energy dispersive X-ray fluorescence (EDXRF) is a well-known technique for non-destructive and in situ analysis of archaeological artifacts both in terms of the qualitative and quantitative elemental composition because of its rapidity and non-destructiveness. In this study EDXRF and realistic Monte Carlo simulation using the X-ray Monte Carlo (XRMC) code package have been combined to characterize a Cu-based bowl from the Iron Age burial from Fareleira 3 (Southern Portugal). The artifact displays a multilayered structure made up of three distinct layers: a) alloy substrate; b) green oxidized corrosion patina; and c) brownish carbonate soil-derived crust. To assess the reliability of Monte Carlo simulation in reproducing the composition of the bulk metal of the objects without recurring to potentially damaging patina's and crust's removal, portable EDXRF analysis was performed on cleaned and patina/crust coated areas of the artifact. Patina has been characterized by micro X-ray Diffractom-etry (μXRD) and Back-Scattered Scanning Electron Microscopy + Energy Dispersive Spectroscopy (BSEM + EDS). Results indicate that the EDXRF/Monte Carlo protocol is well suited when a two-layered model is considered, whereas in areas where the patina + crust surface coating is too thick, X-rays from the alloy substrate are not able to exit the sample.

The coat belt is part of a collection. An investigation with high-precision instruments revealed that it is made of copper alloy with silver coating. The artefact was covered by corrosion and surface defilement. It was broken and deformed at several places, its material was rigid and fragile. Approximately one third of two of its ornaments , 5 of the 24 chain links and 20 of the linking rings were missing. After the dry-cleaning the defilement could be removed with the help of surface-active materials and the corrosion with the help of Argentol. After manual levelling, the amendments were made by a galvanoplastic procedure, receiving a galvanic silver coating. Materials and components were analysed with XRF and EPMA.
A 19. századi nemesi mentekötő anyaga ezüstözött rézötvözet. A restaurálás során a cél az volt, hogy a műtárgy anyagának korróziós folyamatai megszűnjenek , valamint a további károsodások megakadályozása . Feladat volt továbbá , hogy kiállítható állapotba kerüljön a mentekötő , az általa hordozott értékek megőrzésével és
esetlegesen eddig nem ismert információk feltárásával. A láncszemek pótlása galvanizálással történt, rézből, majd, szintén galvanizálással, ezüst bevonatot kaptak. Az anyagvizsgálatok  elektronsugaras mikroanalízissel (EPMA) és röntgen fluoreszcens spektroszkópiával (XRF) készültek.

The artefact, which is from the late 16th century, is one of the beakers in the so-called ‘Szombathely Renaissance Hoard’, an assemblage consisting of 104 pieces.This hoard came to light in November 1963, during an archaeological excavation. Made from silver alloy and with a brim that splays outwards, the beaker is cylindrical. It is partly gilded, on the edges of the chased ornamentation. The presence of mercury, demonstrated in the course of electron radiation microanalysis, proved that the surface was fire gilded.
A 16. század végéről származó műtárgy a 104 darabból álló leletegyüttes, az ún. „Szombathelyi reneszánsz kincslelet” egyik pohara. A leletegyüttes 1963 novemberében a Szombathely, Köztársaság tér (mai nevén Fő tér) 24. számú ház belsőudvarán, az úgynevezett Uránia-udvar nyugati oldalán épületalapozáskor került elő. A pohár restaurálása előtt szükséges volt a tárgyat alkotó anyagokat minél pontosabban azonosítani, mivel ezek alapján lehetett az optimális kezeléseket, eljárásokat kiválasztani. A vizsgálat elektronsugaras mikroanalízissel történt.

-The practical surface analysis method that enables a componential analysis of a single submicrometer inclusion or precipitate on a metallic material surface using an ordinary EDS-SEM- 

  The existence of inclusions or precipitates in metallic materials affects the properties of the materials. Therefore it is vital to analyze the components of them. However an accurate analysis of a single submicrometer inclusion or precpitate on a metallic matrix surface has been difficult by any analytical method. In this article, I will show you a grazing exit electron probe microanalysis (GE-EPMA) technique as the sole method to accurately analyze such a single submicrometer inclusion or precipitate appeared on an etched metallic matrix surface. I would be happy if you could enjoy the simplicity and the effectivity of the GE-EPMA.

This is the first structural refinement of the mineral
wilkinsonite, Na2Fe4
2+Fe2
3+Si6O20. Wilkinsonite is a member
of the aenigmatite group and consists of bands of Fe octahedra
connected to eight-coordinated Na polyhedra forming sheets
parallel to (011), which are interconnected by chains of
[Si6O18]1 and Fe octahedra. The site occupancies of the
different valence states of Fe have been determined from
bond distances and bond valence