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We determined the physical conditions at the time of its entrapment for an inclusion pair hosted in a Siberian diamond (Udachnaya kimberlite) and found that it equilibrated under relatively oxidized conditions, near the enstatite–magnesite–olivine–diamond (EMOD) buffer, similarly to Udachnaya xenoliths originating from comparable depths. These results can be reconciled with models suggesting relatively oxidized, water-rich CHO fluids as the most likely parents for lithospheric diamonds.

Amphibole–liquid partitioning of elements of geological relevance is experimentally derived at conditions compatible with those of the Earth's upper mantle. Experiments are carried out at different oxygen fugacity conditions and variable Cl content in order to investigate their influence on the amphibole–liquid partition coefficients. Our results point to the capability of amphibole to act as filter for trace elements at upper-mantle conditions, oxidized conditions, and Cl-rich environments.

On the west coast of the German North Sea island of Sylt, an electrum–quartz pebble weighing 10.4 g was discovered in a cliff of Saalian glaciogenic sediments. This is an unusually large and rare precious metal to find. Within our paper we document and characterize this discovery. An attempt to investigate its provenance points towards a southern Norwegian origin. This leads to the conclusion that ice advance events were involved in transporting this pebble from Norway to Germany.

Hydrous defects in quartz contain important information regarding the origin and history of individual grains. This article summarises the findings from experimental work and analysis of natural material over the past 60 years, and results are interpreted with respect to igneous, metamorphic, and sedimentary processes.