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The characterization of freshly cleaved mica surfaces for surface structure and chemical composition was briefly reviewed and focused on surface crystal chemistry using X-ray photoelectron spectroscopy (XPS) and other surface-sensitive techniques. This paper considers micas, which are useful as a first approximation for the behavior of many clay surfaces. Emphasis was given to phyllosilicate XPS binding energies (''chemical shift''), which were described and used to obtain oxidation state, layer charge, and chemical bonding information from the chemical shifts of different peaks. The chemical shift of the Si2p binding-energy to lower values can result from a negative charge increase because of Si4+ replacement by Al3+ and/or Fe3+. The apparent interlayer coordination number reduction from twelve to eight at muscovite and tetraferriphlogopite (001) surfaces was indicated by the XPS measured K2p binding-energy and is consistent with bond relaxation. Although chemical shifts are valuable to distinguish chemical bonding and oxidation state, chemical shifts usually cannot distinguish between different Al coordination environments where Al is in both tetrahedral and octahedral sites.

Birnessite-like minerals are among the most common Mn oxides in surficial soils and sediments, and they mediate important environmental processes (e.g., biogeochemical cycles, heavy metal confinement) and have novel technological applications (e.g., water oxidation catalysis). Ca is the dominant interlayer cation in both biotic and abiotic birnessites, especially when they form in association with carbonates. The current study investigated the structures of a series of synthetic Ca-birnessite analogs prepared by cation-exchange with synthetic Na-birnessite at pH values from 2 to 7.5. The resulting Ca-exchanged birnessite phases were characterized using powder X-ray diffraction and Rietveld refinement, Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning and transmission electron microscopy. All samples synthesized at pH values greater than 3 exhibited a similar triclinic structure with nearly identical unit-cell parameters. The samples exchanged at pH 2 and 3 yielded hexagonal structures, or mixtures of hexagonal and triclinic phases. Rietveld structure refinement and X-ray photoelectron spectroscopy showed that exchange of Na by Ca triggered reduction of some Mn3+, generating interlayer Mn2+ and vacancies in the octahedral layers. The triclinic and hexagonal Ca-birnessite structures described in this study were distinct from Na- and H-birnessite, respectively. Therefore, modeling X-ray absorption spectra of natural Ca-rich birnessites through mixing of Na- and H-birnessite end-members will not yield an accurate representation of the true structure.

The very rapid energy release from impact events, such as those resulting from lightning strikes or meteorites, can drive a variety of physical and chemical processes which alter rocks and result in the formation of natural glasses (i.e., fulgurites and tektites). Fulgurite is the vitrified soil, sand, or rock resulting from lightning strikes. A thunderbolt is associated with air temperatures of up to 105 K, which can heat rocks to >2000 K within tens of microseconds. The rapid fusing and subsequent quenching of the surface of the rock leaves a distinctive, thin, garbled coating composed of a glassy to fine‐grained porous material. Previous studies on rock fulgurites found planar deformation features in quartz crystals within the target rock substrate, evidence of strong shock waves during fulgurite formation. In this paper, we simulated the shock pressure and temperature caused by an idealized lightning impact on rocks and compared the model results with observations on rock fulgurites from the literature. Our model results indicate that a lightning strike can cause >7 GPa pressure on the rock surface, generate a layer of fulgurite (of radius ∼9 cm), and leave a burned region (of radius ∼11 cm). The fulgurites found on rock surfaces share many features with sand fulgurites, but their spatial distribution is completely different, as sand fulgurites are hollow tube structures. Our study on rock fulgurites provides an indirect constraint on the energy of a lightning event and also demonstrates that the presence of shock features in rocks cannot be taken as unequivocal evidence for impact events.

Along glaciated margins, ratios of meteoric cosmogenic beryllium‐10, 10Be, normalized to its stable isotope, 9Be, reflect an environmental signal, driven ultimately by climatic change. We explore the application of this isotopic pair as a proxy for East Antarctic Ice Sheet dynamics. We analyze 10Be/9Be in middle Pliocene glaciomarine sediments offshore the Wilkes Land Region (Integrated Ocean Drilling Program (IODP) Site U1361A) and examine our new record alongside existing biochemical/geochemical records (Ba/Al, opal %wt, εNd, and 87Sr/86Sr). 10Be/9Be ratios reach local maxima during pulsed, mild warming events and are strongly correlated with existing records that indicate concurrent ice sheet retraction and increased bioproductivity. We suggest climate change as the primary driver of the 10Be/9Be record near glaciated margins, whereby increased warming drives ice sheet retraction, discharging freshwaters and diluting the open ocean 10Be/9Be signal recorded in authigenic minerals.

Because of their many novel and advanced applications, there is increasing interest in layer silicates from the scientific and technical communities. Appropriate application of these minerals requires deep understanding of their properties and of the processes where they are involved. This chapter, by providing fundamental definitions and crystal structural and chemical data pertaining to layer silicates, aims to introduce this field to new researchers and technicians, by describing the fundamental features leading to different behaviours of layer silicates in different natural or technical processes. The subject addressed is vast and so the reader is referred in some cases to work already published. The focus here is on layer silicates for which detailed crystal structures are given in the literature and which are likely to be used in an applied way in the future. Layer-silicate minerals fulfilling these requirements are: (1) kaolin-serpentine group(e.g. kaolinite, dickite, nacrite, halloysite, hisingerite, odinite, lizardite, berthierine, amesite, cronstedtite, nepouite, kellyite, fraipontite, brindleyite, guidottiite, bementite, greenalite, caryopilite; minerals of the pyrosmalite series); (2) talc and pyrophyllite groups (e.g. pyrophyllite, ferripyrophyllite, willemseite); (3) mica group (i.e. some recent advances in crystal chemistry and structure of dioctahedral and trioctahedral micas); (4) smectite group (e.g. montmorillonite, saponite, hectorite, sauconite, stevensite, swinefordite); (5) vermiculite group; (6) chlorite group (e.g. trioctahedral chlorite such as clinochlore, di,trioctahedral and dioctahedral chlorites such as cookeite and sudoite); (7) some 2:1 layer silicates involving a discontinuous octahedral sheet and a modulated tetrahedral sheet such as kalifersite, palygorskite and sepiolite; and (8) imogolite and allophane.

Social and emotional learning (SEL) strategies develop skills linked to cognitive development, encourage student focus and motivation, improve relationships between students and teachers, and increase student confidence and success. More attention should be paid to students’ emotions in higher education to enhance students’ engagement in the classroom and improve social awareness (i.e., respecting others, understanding other perspectives, providing help to those who need it), motivation, and academic achievement. This article focuses on the implementation of practices that promote SEL in higher education and science, technology, engineering, and mathematics (STEM) programs. The paper aims to assess the academic and behavioral-related outcomes of applying SEL in mineralogy, an Earth science introductory course in a four-year university. The results of the present paper reveal that instructional practices supporting SEL are suited for engaging and stimulating learners’ multiple intelligences. The observed student course assessment performance suggests that integrating SEL may be a viable strategy for promoting student interest in science, building stress resilience, and creating more positive engagement with students. The instructional practices reported in this paper could support science instructors in designing teaching methods that promote self-management and social awareness to increase students’ academic outcomes.

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