OH defect contents in quartz in a granitic system at 1-5 kbar.

Quartz is able to incorporate trace elements (e.g., H, Li, Al, B) depending on the formation conditions (P, T, and chemical system). Consequently, quartz can be used as a tracer for petrogenetic information of silicic plutonic bodies. In this experimental study, we provide the first data set on the OH defect incorporation in quartz from granites over a pressure/temperature range realistic for the emplacement of granitic melts in the upper crust. Piston cylinder and internally heated pressure vessel synthesis experiments were performed in a water-saturated granitic system at 1-5 kbar and 700-950 °C. Crystals from successful runs were analysed by secondary ion mass spectrometry (SIMS) and Fourier transform infrared (FTIR) spectroscopy, and their homogeneity was verified by FTIR imaging. IR absorption bands can be assigned to specific OH defects and analysed qualitatively and quantitatively and reveal that (1) the AlOH band triplet at 3310, 3378 and 3430 cm-1 is the dominating absorption feature in all spectra, (2) no simple trend of total OH defect incorporation with pressure can be observed, (3) the LiOH defect band at 3470-3480 cm-1 increases strongly in a narrow pressure interval from 4 kbar (220 µg/g H2O) to 4.5 kbar (500 µg/g H2O), and declines equally strong towards 5 kbar (180 µg/g H2O). Proton incorporation is charge balanced according to the equation H+ + A+ + P5+ = M3+ + B3+, with A+ = alkali ions and M3+ = trivalent metal ions.

OH-defects in multiple-doped orthoenstatite at 4-8 GPa: filling the gap between pure and natural systems.

OH-defects in orthoenstatite were studied experimentally between 4 and 8 GPa at 1150 °C in the system CaO-MgO-Al2O3-SiO2-Cr2O3-Na2O, leading to phase assemblages enstatite ± forsterite ± diopside ± garnet. In enstatite coexisting with garnet, total OH is negatively correlated with pressure. Conversely, in Al-poor systems without garnet, total OH is positively correlated with pressure, and both trends intersect around 8 GPa and ~1000 wt ppm H2O. IR-spectra of enstatite reveal several pressure sensitive features, such as (1) the absorbance of the absorption band at 3687 cm-1, (2) the band position near 3400 cm-1 and (3) the ratio (A3240-3570/A3240-3730) and their application as geobarometer in natural samples are evaluated. For garnet-bearing phase assemblages, the band ratio (A3240-3570/A3240-3730) in orthoenstatite defines a pressure trend in between that observed in the pure system MgO-SiO2-H2O and that found in orthopyroxenes from natural mantle peridotites, suggesting that the application of IR-spectra as proxy for pressure is justified.

Experimental partitioning of halogens and other trace elements between olivine, pyroxenes, amphibole and aqueous fluid at 2 GPa and 900-1,300 °C.

We present new partition coefficients for various trace elements including Cl between olivine, pyroxenes, amphibole and coexisting chlorine-bearing aqueous fluid in a series of high-pressure experiments at 2 GPa between 900 and 1,300 °C in natural and synthetic systems. Diamond aggregates were added to the experimental capsule set-up in order to separate the fluid from the solid residue and enable in situ analysis of the quenched solute by LA-ICP-MS. The chlorine and fluorine contents in mantle minerals were measured by electron microprobe, and the nature of OH defects was investigated by infrared spectroscopy. Furthermore, a fluorine-rich olivine from one selected sample was investigated by TEM. Results reveal average Cl concentrations in olivine and pyroxenes around 20 ppm and up to 900 ppm F in olivine, making olivine an important repository of halogens in the mantle. Chlorine is always incompatible with Cl partition coefficients DClolivine/fluid varying between 10-5 and 10-3, whereas DClorthopyroxene/fluid and DClclinopyroxene/fluid are ~10-4 and DClamphibole/fluid is ~5 × 10-3. Furthermore, partitioning results for incompatible trace element show that compatibilities of trace elements are generally ordered as Damph/fluid ≈ Dcpx/fluid > Dopx/fluid > Dol/fluid but that Dmineral/fluid for Li and P is very similar for all observed silicate phases. Infrared spectra of olivine synthesized in a F-free Ti-bearing system show absorption bands at 3,525 and ~3,570 cm-1. In F ± TiO2-bearing systems, additional absorption bands appear at ~3,535, ~3,595, 3,640 and 3,670 cm-1. Absorption bands at ~3,530 and ~3,570 cm-1, previously assigned to humite-like point defects, profit from low synthesis temperatures and the presence of F. The presence of planar defects could not be proved by TEM investigations, but dislocations in the olivine lattice were observed and are suggested to be an important site for halogen incorporation in olivine.

Application of mid-infrared microscopic imaging for the diagnosis and classification of human lymphomas.

Mid-infrared (MIR) microscopic imaging of indolent and aggressive lymphomas was performed including formalin-fixed and paraffin-embedded samples of six follicular lymphomas and 12 diffuse large B-cell-lymphomas as well as reactive lymph nodes to investigate benefits and challenges for lymphoma diagnosis. MIR images were compared to defined pathological characteristics such as indolent versus aggressive versus reactive, germinal centre versus activated cell-of-origin (COO) subtypes, or a low versus a high proliferative index and level of PD-L1 expression. We demonstrated that MIR microscopic imaging can differentiate between reactive lymph nodes, indolent and aggressive lymphoma samples. Also, it has potential to be used in the subtyping of lymphomas, as shown with the differentiation between COO subtypes, the level of proliferation and PD-L1 expression. MIR microscopic imaging is a promising tool for diagnosis and subtyping of lymphoma and further evaluation is needed to fully explore the advantages and disadvantages of this method for pathological diagnosis.

Intermediate states on the way to edge-sharing BO4 tetrahedra in M6B22O39·H2O (M=Fe, Co).

The new borates Fe(II)(6)B(22)O(39)·H(2)O (colourless) and Co(II)(6)B(22)O(39)·H(2)O (dichroic: red/bluish) were synthesised under the high-pressure/high-temperature conditions of 6 GPa and 880 °C (Fe)/950 °C (Co) in a Walker-type multi-anvil apparatus. The compounds crystallise in the orthorhombic space group Pmn2(1) (Z=2) with the lattice parameters a=771.9(2), b=823.4(2), c=1768.0(4) pm, V=1.1237(4) nm(3), R(1)=0.0476, wR(2)=0.0902 (all data) for Fe(6)B(22)O(39)·H(2)O and a=770.1(2), b=817.6(2), c=1746.9(4) pm, V=1.0999(4) nm(3), R(1)=0.0513, wR(2)=0.0939 (all data) for Co(6)B(22)O(39)·H(2)O. The new structure type of M(6)B(22)O(39)·H(2)O (M=Fe, Co) is built up from corner-sharing BO(4) tetrahedra and BO(3) groups, the latter being distorted and close to BO(4) tetrahedra if additional oxygen atoms of the neighbouring BO(4) tetrahedra are considered in the coordination sphere. This situation can be regarded as an intermediate state in the formation of edge-sharing tetrahedra. The structure consists of corrugated multiple layers interconnected by BO(3)/BO(4) groups to form Z-shaped channels. Inside these channels, iron and cobalt show octahedral (M1, M3, M4, M5) and strongly distorted tetrahedral (M2, M6) coordination by oxygen atoms. Co(II)(6)B(22)O(39)·H(2)O is dichroic and the low symmetry of the chromophore [Co(II)O(4)] is reflected by the polarised absorption spectra (Δ(t)=4650 cm(-1), B=878 cm(-1)).

Variations of OH defects and chemical impurities in natural quartz within igneous bodies.

In this study, we present the first systematic dataset on natural variations of OH defect and trace element contents in quartz within igneous bodies. Samples were derived from bore holes of two plutonic bodies from the Krusné Hory/Erzgebirge (German-Czech border), representing typical A-type (Cínovec/Zinnwald granite cupola) and S-type (Podlesí Stock) granite intrusions. Fourier Transform Infrared spectroscopy of quartz was used to investigate the sample set with regard to its OH defect speciation and content. For Zinnwald quartz, IR absorption spectra reveal different lithologies due to changes of the OH defect inventory, enabling a subdivision of the granitic body: (1) hydrothermal greisen quartz of the uppermost part of the intrusion have low OH defect contents (average of 15 µg/g H2O); (2) zinnwaldite granite quartz vary strongly in defect content and show the highest content of the dataset (10-70 µg/g H2O); (3) quartz from an underlying biotite granite have slightly lower, but very uniform contents down to the bottom of the borehole at 1600 m (average 20 µg/g H2O). Infrared spectra of Podlesí quartz reveal a gradual increase in total defect water content with increasing depth over 350 m (30-55 µg/g H2O). Lithium contents in quartz samples from the uppermost part of the Zinnwald intrusion correlate with the occurrence of Li-specific OH defects, while cathodoluminescence (CL) images do not show specific differences. Our findings evidence the potential of OH defects in quartz as a tool to decipher differentiation trends in igneous bodies, and the application of their eroded material for provenance analyses.

Experimental chlorine partitioning between forsterite, enstatite and aqueous fluid at upper mantle conditions.

Cl partition coefficients between forsterite, enstatite and coexisting Cl-bearing aqueous fluids were determined in a series of high pressure and temperature piston cylinder experiments at 2 GPa between 900 and 1300 °C in the system MgO-SiO2-H2O-NaCl-BaO-C±CaCl2±TiO2±Al2O3±F. Diamond aggregates were added to the experimental capsule set-up in order to separate the fluid from the solid residue and enable in situ analysis of the quenched solute by LA-ICP-MS. The chlorine content of forsterite and enstatite was measured by electron microprobe, and the nature of hydrous defects was investigated by infrared spectroscopy. Partition coefficients show similar incompatibility for Cl in forsterite and enstatite, with DClfo/fl = 0.0012 ± 0.0006, DClen/fl = 0.0018 ± 0.0008 and DClfo/en = 1.43 ± 0.71. The values determined for mineral/fluid partitioning are very similar to previously determined values for mineral/melt. Applying the new mineral/fluid partition coefficients to fluids in subduction zones, a contribution between 0.15% and 20% of the total chlorine from the nominally anhydrous minerals is estimated. Infrared spectra of experimental forsterite show absorption bands at 3525 and 3572 cm-1 that are characteristic for hydroxyl point defects associated with trace Ti substitutions, and strongly suggest that the TiO2 content of the system can influence the chlorine and OH incorporation via the stabilization of Ti-clinohumite-like point defects. The water contents for coexisting forsterite and enstatite in some runs were determined using unpolarized IR spectra and calculated water partition coefficients [Formula: see text] are between 0.01 and 0.5.