Mineral assemblages and chemical composition of bavenite-bohseite were examined at 15 granitic pegmatites from the Bohemian Massif, Czech Republic. Three types distinct in their relation to primary Be-precursors, mineral assemblages, morphology, and origin were recognised. (i) Primary hydrothermal bavenite-bohseite crystallised in miarolitic pockets from residual pegmatite fluids. Secondary bavenite-bohseite occurs in two distinct types: (ii) a proximal type spatially restricted to pseudomorphs after a primary Be-mineral (beryl > phenakite, helvine-danalite), and (iii) a distal type on brittle fractures and fissures of host pegmatite. Their mineral assemblages are highly variable: (i) axinite-(Mn), smectite, calcite, pyrite, (ii) bertrandite, milarite, secondary beryl, bazzite, K-feldspar, muscovite-illite, scolecite, gismondine-(Ca), analcime, chlorite, and (iii) muscovite, albite, quartz, epidote, pumpellyite-(Mg), pumpellyite-(Fe 3+ ), titanite, chlorite. The electron probe micro-analyses showed in addition to major constituents (Si, Ca, Al) also minor concentrations (in apfu) of Na (≤0.24), Fe (≤0.10), Mn (≤0.10), and F (≤0.36). The (i) hydrothermal miarolitic bavenite-bohseite is mostly Al-rich (2.00-0.67 apfu) relative to (ii) proximal bavenite-bohseite and bohseite after beryl, phenakite and helvine-danalite (1.56-0.46, 0.70-0.05, 1.02-0.35 apfu, respectively) and

Recently found historical jewellery (Czech Republic) was subjected to detailed analyses to determine the gem inlays and the gold framework in which they are embedded. Such find fits into European jewellery archaeological artefacts containing similar stones from around the fifth century CE. The gemstones were analysed with optical microscopy and Raman micro-spectroscopy to determine their mineralogical characteristics and to find out typical structural-chemical differences based on which their provenance can be found. The results of this measurement discovered two main types of minerals from the garnet group, almandine and pyrope, where pyropes have been identified as Bohemian garnets thanks to the typical photoluminescence (PL) of chromium and vanadium impurities. The craftsmanship and processing of the goldsmith work were studied using X-ray computed tomography. Such a technique is an excellent contribution for detecting and visualising the internal parts hidden behind the placement of the stones. For this reason, 3D visualisation was used to describe and better understand all preserved parts. According to this object's very high cultural and historical value, the chosen methods are suitable for non-destructive study while proving to be essential to deepen our knowledge in archaeometric investigations focused on jewellery from Late Antiquity (with possible application to the jewellery from other periods). Based on the findings presented in this study, it is one of the world's oldest documented items using Bohemian garnets in jewellery. These findings underscore the tremendous economic and political importance of Bohemian garnet mineral resources altogether, with a second completely different type of garnet believed to have originated in distant India or Sri Lanka that was used in jewellery across Europe in Late Antiquity.

A second study of ferriallanite-(Ce) from Nya Bastnäs, Sweden, extends current data by using electron probe micro-analysis (EPMA), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis and brings new insights about its crystal chemistry obtained by Raman spectroscopy. The study presents the first Raman spectra for ferriallanite-(Ce) member of the allanite group (not considering the rather low-quality spectra published in preceding papers). The material does not show significant radiation damage, which is rare as allanite-group minerals often have undergone metamictisation due to significant amounts of incorporated radionuclides (U, Th). Some interior regions show pronounced zoning that correlates with variations in Raman-band positions. In spite of its significant REE content, the material is virtually non-luminescent. New additional data for allanite-(Ce) from Oßling, Germany and Domanínek, Czech Republic are also presented, which were used for comparison.

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