University, Diss., 2004--Frankfurt (Main).

Jena, Univ., Diss., 2009.

Scanning electron microscopy based automated mineralogy (SEM-AM) is a combined analytical tool initially designed for the characterisation of ores and mineral processing products. Measurements begin with the collection of backscattered electron (BSE) images and their handling with image analysis software routines. Subsequently, energy dispersive X-ray spectra (EDS) are gained at selected points according to the BSE image adjustments. Classification of the sample EDS spectra against a list of approved reference EDS spectra completes the measurement. Different classification algorithms and four principal SEM-AM measurement routines for point counting modal analysis, particle analysis, sparse phase search and EDS spectral mapping are offered by the relevant software providers. Application of SEM-AM requires a high-quality preparation of samples. Suitable non-evaporating and electron-beam stable epoxy resin mixtures and polishing of relief-free surfaces in particles and materials with very different hardness are the main challenges. As demonstrated by case examples in this contribution, the EDS spectral mapping methods appear to have the most promising potential for novel applications in metamorphic, igneous and sedimentary petrology, ore fingerprinting, ash particle analysis, characterisation of slags, forensic sciences, archaeometry and investigations of stoneware and ceramics. SEM-AM allows the quantification of the sizes, geometries and liberation of particles with different chemical compositions within a bulk sample and without previous phase separations. In addition, a virtual filtering of bulk particle samples by application of numerous filter criteria is possible. For a complete mineral phase identification, X-ray diffraction data should accompany the EDS chemical analysis. Many of the materials which potentially could be characterised by SEM-AM consist of amorphous and glassy phases. In such cases, the generic labelling of reference EDS spectra and their subsequent target component grouping allow SEM-AM for interesting and novel studies on many kinds of solid and particulate matter which are not feasible by other analytical methods.

This study investigates various glass objects from the 17th and 18th centuries in Thuringia to gain insight into their manufacturing techniques. The objects include glass beads from the Roten Schmelzzimmer and diverse glass objects from the Schwarzburg-Sondershausen collection. The analytical methods include optical microscopy, CT, SEM-EDX, LA-ICP-MS and Raman spectroscopy. The glass beads from the Roten Schmelzzimmer were identified as soda-lime- and high-lead-silicate glasses, which were made using highly pure sands and halophytic plant ashes as a fluxing agent. These recipes are characteristic from the Mediterranean region. The beads were coloured in 11 different colours with copper, cobalt, manganese, iron, and were possibly opacified with salt and tartrate. The analysed glass objects from the Schwarzburg collection were made using different recipes based on potash-lime-silicate glass with high amounts of potash and calcium, and calcinated-bone ashes as a white opacifier, characteristic of central Europe.