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Physical samples and their associated (meta)data underpin scientific discoveries across disciplines, and can enable new science when appropriately archived. However, there are significant gaps in community practices and infrastructure that currently prevent accurate provenance tracking, reproducibility, and attribution. For the vast majority of samples, descriptive metadata is often sparse, inaccessible, or absent. Samples and associated (meta)data may also be scattered across numerous physical collections, data repositories, laboratories, data files, and papers with no clear linkages or provenance tracking as new information is generated over time. The Physical Samples Curation Cluster has therefore developed ‘A Scientific Author Guide for Publishing Open Research Using Physical Samples.’ This involved synthesizing existing practices, community feedback, and assessing real-world examples to identify community and infrastructure needs. We identified areas of work needed to enable authors to efficiently reference samples and related data, link related samples and data, and track their use. Our goal is to help improve the discoverability, interoperability, use of physical samples and associated (meta)data into the future. 

Recycling is not just for plastic. Did you know that the Earth recycles? Recycling happens because the outer part of the planet is made up of large moving pieces of rock. Some of these pieces, called tectonic plates, sink deep down into the Earth. The deeper they go, the more heat and pressure they experience. This causes chemical reactions, including melting of the minerals that make up the rocks. Elements and water trapped inside the melting minerals are released and erupt from volcanoes, returning to the surface. The Earth has recycled! In this article, we present new research on a mineral called lawsonite. Lawsonite only forms in plates that dive into the Earth. Lawsonite has returned to the Earth’s surface in a few rare places where we can collect and analyze it. The composition of elements inside the lawsonite mineral help us understand the deep part of the Earth recycling system. 

Abstract In orogens worldwide and throughout geologic time, large volumes of deep continental crust have been exhumed in domal structures. Extension‐driven ascent of bodies of deep, hot crust is a very efficient mechanism for rapid heat and mass transfer from deep to shallow crustal levels and is therefore an important mechanism in the evolution of continents. The dominant rock type in exhumed domes is quartzofeldspathic gneiss (typically migmatitic) that does not record its former high‐pressure (HP) conditions in its equilibrium mineral assemblage; rather, it records the conditions of emplacement and cooling in the mid/shallow crust. Mafic rocks included in gneiss may, however, contain a fragmentary record of a HP history, and are evidence that their host rocks were also deeply sourced. An excellent example of exhumed deep crust that retains a partial HP record is in the Montagne Noire dome, French Massif Central, which contains well‐preserved eclogite (garnet+omphacite+rutile+quartz) in migmatite in two locations: one in the dome core and the other at the dome margin. Both eclogites recordP ~ 1.5 ± 0.2 GPa atT ~ 700 ± 20°C, but differ from each other in whole‐rock and mineral composition, deformation features (shape and crystallographic preferred orientation, CPO), extent of record of prograde metamorphism in garnet and zircon, and degree of preservation of inherited zircon. Rim ages of zircon in both eclogites overlap with the oldest crystallization ages of host gneiss atc.310 Ma, interpreted based on zircon rare earth element abundance in eclogite zircon as the age of HP metamorphism. Dome‐margin eclogite zircon retains a widespread record of protolith age (c.470–450 Ma, the same as host gneiss protolith age), whereas dome‐core eclogite zircon has more scarce preservation of inherited zircon. Possible explanations for differences in the two eclogites relate to differences in the protolith mafic magma composition and history and/or the duration of metamorphic heating and extent of interaction with aqueous fluid, affecting zircon crystallization. Differences in HP deformation fabrics may relate to the position of the eclogite facies rocks relative to zones of transpression and transtension at an early stage of dome development. Regardless of differences, both eclogites experienced HP metamorphism and deformation in the deep crust atc.310 Ma and were exhumed by lithospheric extension—with their host migmatite—near the end of the Variscan orogeny. The deep crust in this region was rapidly exhumed from ~50 to <10 km, where it equilibrated under low‐P/high‐Tconditions, leaving a sparse but compelling record of the deep origin of most of the crust now exposed in the dome.