Abstract Evaporite minerals can capture and entomb organic matter within their intercrystalline and intracrystalline structure because they precipitate relatively quickly (nomenclature adopted from Schopf et al. (2012), https://doi.org/10.1089/ast.2012.0827 ). Thus, evaporite minerals constitute a target for biosignature investigation on Earth and Mars, where evaporitic deposits are known to exist. However, little is known about the process of organic preservation and detection in evaporites, or the stability of such molecules when exposed to significant UV radiation as would be present on the surface of Mars. Here, we investigate the incorporation of β ‐carotene into halite (NaCl) by growing halite in the lab in the presence of know concentrations of β ‐carotene and examining the resultant precipitated crystals and fluid inclusions via Raman spectroscopy. Following brine evaporation, the experimental β ‐carotene‐containing halite was exposed to UV‐C to simulate conditions on the Martian surface. Results reveal that β ‐carotene has a strong Raman signature that remains intact even when entombed in halite. In particular, fluid inclusions within the halite displayed particularly strong β ‐carotene Raman signatures after UV‐C exposure. Little change was observed even after several days of UV‐C delivery. Our results reveal that complex organic molecules like β ‐carotene should be preserved well in halite (especially in fluid inclusions) and that halite does provide protection from organic matter degradation from UV‐C radiation. Thus, evaporites constitute a good target for the search for biomarkers on Mars. These findings will allow for proper criteria for the discovery of any potential physical biosignature and chemical biomarker that would be on active ocean worlds (Europa, Enceladus) and for future Mars subsurface drilling missions.

Subduction of serpentinized mantle lithosphere delivers nitrogen (N) into the mantle, but the residency and speciation of N therein remain largely unknown. Serpentine, talc, and chlorite have been proposed as likely hosts in K-poor ultramafic rocks due to the minerals' sheet-like structures and the ability for N to reside in interlayer sites. In this study, we explore whether these three minerals are the primary hosts of N in subduction-related mantle lithosphere and metasomatized hybrid rocks (serpentinites, talc schists, and chlorite schists) by analyzing the N concentrations and isotope compositions of paired whole-rock and phyllosilicate mineral separates. Mineralogy of nine samples and sixteen mineral separates from ultramafic units in Syros, Greece, and Pam Peninsula, New Caledonia, were characterized by petrography and X-ray diffraction (XRD) prior to N analyses. Whole-rock N concentrations are from 25 to 102 & micro;g/g and N-isotopes compositions (S15Nair) range from-0.2 to +6.9%o, whereas mineral separates contain 8 & micro;g/g to 176 & micro;g/g N with S15N of-1.2 to +7.0%o. These results show that ultramafic rocks and phyllosilicate minerals from subduction zone settings contain 10's to 100's of & micro;g/g of N, and have S15N consistent with mixing with a sedimentary-derived fluid. However, mineral separates show variable N and S15N enrichment or depletion relative to their respective whole-rocks, with most separates containing <= 40% of the whole-rock N and systematically lower S15N values. These data indicate that, for the majority of the samples, a considerable fraction of the N is hosted in minerals or sites within the whole-rock not captured in the mineral separates. We combine textural observations and geochemical correlations to propose that the discrepancy between the whole-rocks and their mineral separates can be explained by heterogeneous N distribution among different generations of phyllosilicate minerals within single samples and/or significant N hosted in other minerals and sites (e.g., accessory phases or interstitial phases). Further investigation is required to distinguish between these possibilities, with implications for N speciation and stability during subduction zone metamorphism from the forearc to depths beneath arcs and beyond.

Cadvanite (IMA2025-005), CdV2O6, is a new mineral discovered at the Burro mine, Slick Rock district, San Miguel County, Colorado, USA. It was found in a secondary efflorescent assemblage on matrix composed of quartz grains, covellite-klockmannite, and cadmoselite and it is associated with brochantite, chalcomenite, clinochalcomenite, gypsum, and volborthite. The mineral occurs as poorly formed brownish-yellow blades. The streak is pale yellow, the luster is dull, silky, or adamantine, the Mohs hardness is about 2 & half;-3, the tenacity is brittle, the fracture is splintery, and there are probably two cleavages, possibly {100} and {001}. The calculated density is 4.210 g/cm(3). Electron probe microanalysis provided the empirical formula Cd1.00V2.00O6. Cadvanite is monoclinic, space group C2/m, a = 9.831(10), b = 3.6220(9), c = 7.051(5) & Aring;, beta = 103.97(2)degrees, V = 243.65(7) & Aring;(3), and Z = 2. In the crystal structure (R-1 = 0.0505 for 1210 I > 2 sigma(I) reflections), Cd2+O6 octahedra form a straight edge-sharing chain and the V5+O5 polyhedra form a zig-zag edge-sharing [VO3](-) chain. The two chains link to one another by corner sharing to form a three-dimensional framework.

Abstract Mineral dust is sourced from arid regions around the globe, and its composition impacts regional and global environments by affecting radiation balance, cloud formation, nutrient deposition, and snowmelt. As such, mineral dust plays a key role in Earth's energy and biogeochemical budgets. Global remote sensing of dust source regions have the potential to significantly improve our understanding of mineral dust composition and its environmental impacts. While, visible to shortwave infrared data in remote measurements effectively map surface mineralogy for large swaths of mineral groups, they struggle to detect quartz and feldspar, the two most abundant minerals on Earth's surface. Broadband thermal infrared remotely sensed data are capable of remote measurements of quartz and feldspar, but on their own are limited in their ability to resolve confounding factors including other minerals and vegetation. Here, we demonstrate the utility of joint visible to thermal infrared (VTIR) data by leveraging existing remote sensing data products and spectral libraries in a Monte Carlo spectral mixing analysis to remotely retrieve global quartz and feldspar areal distributions with grain size information. Resulting latitudinal and regional‐scale distributions are consistent with expectations based on geological settings. Using a case study, we demonstrate our VTIR‐based unmixing strategy is theoretically capable of further separating grain sizes and chemistries. These results highlight the utility of VTIR data, the value in further collection of these data as part of future space‐based Earth observations, and the need for improved VTIR spectral libraries for interpretation.

The new mineral svornostite-(NH4) (IMA2024-068), (NH4)(2)Mg(UO2)(2)(SO4)(4)(H2O)(8), was found in the Blue Lizard mine, San Juan County, Utah, USA, where it occurs as sprays and subparallel groups of yellow blades in a secondary assemblage with ammoniozippeite, blodite, boussingaultite, gypsum, hexahydrite, kr & ouml;hnkite, pl & aacute;& scaron;ilite and quartz. The streak is very pale yellow. Crystals are transparent with vitreous lustre. The tenacity is brittle, the Mohs hardness is similar to 2 1/2, the fracture is curved. The mineral is soluble in H2O and has a measured density of 3.06(2) gcm(-3). The mineral is optically biaxial (+) with alpha = 1.560(2), beta = 1.564(2), gamma = 1.589(2); 2V = 43(1)degrees; orientation: X = a, Y = b, Z = c; pleochroism: X colourless, Y yellow, Z yellow; X < Y approximate to Z. Electron microprobe analyses provided [(NH4)(1.895)Na0.065K0.040](Sigma 2.000)(Mg0.755Mn0.252)(Sigma 1.007)(U0.996O2)(2)(S1.002O4)(4)(H1.998O)(8). Svornostite-(NH4) is orthorhombic, Pmn2(1), a = 13.0259(9), b = 8.2909(4), c = 11.2589(4) & Aring;, V = 1215.92(11) & Aring;(3) and Z = 2. The crystal structure (R-1 = 0.0243 for 2222 I > 2 sigma(I) reflections) contains uranyl-sulfate chains that are linked into sheets by MgO2(H2O)(4) octahedra and 9- and 10-coordinated NH4+ groups. The sheet has the same topology as the sheets in several synthetic uranyl selenates. Svornostite-(NH4) is a member of the newly established svornostite group, which also includes svornostite-(K), oldsite-(K), rietveldite and zincorietveldite.

Our investigation in Mars-relevant terrestrial environments where biological material is entombed within rapidly precipitated evaporite crystals has given us the ability to evaluate the preservation potential of a hypersaline brine system in advance of interrogating similar environments on Mars. These evaporite minerals, halite (NaCl) and gypsum (CaSO4), have been found to host authigenic fluid inclusions over geologic time, with cellular life and carotenoid pigments that are understudied in the planetary context. Great Salt Lake provides an excellent site to test the ability to detect organic matter in Mars-relevant evaporite crystals. DNA was extracted to determine which microbial clades were present and assess the attenuation of DNA preservation from the host fluid of the lake to the mineral. Raman spectroscopy was used to investigate the presence of pigments that have longer preservation potential than DNA. Compared with the water column, evaporite minerals preserve higher volumes of DNA and associated biochemistry, whereas entombed fluid inclusions preserve even higher magnitudes of both biomarkers. This indicates organic addition and continued preservation as the crystals precipitate from the fluid, which was later confirmed as micrometer-scale environments continued to maintain the ecology within closed-system fluid inclusions. Raman analyses of halite revealed the presence of β-carotene and bacterioruberin, consistent with the presence of carotenoid-generating bacteria and archaea in this hypersaline environment, which are characterized by pink coloration. The continued preservation of these chemical biomarkers over time has led to the formation of physical biosignatures within the evaporite record. Given that these same minerals are present in ancient fluvial sites across Mars, halite and gypsum are ideal candidates for future in situ observation and should be considered high priority for sample return missions.

The new mineral svornostite-(NH 4 ) (IMA2024-068), (NH 4 ) 2 Mg(UO 2 ) 2 (SO 4 ) 4 (H 2 O) 8 , was found in the Blue Lizard mine, San Juan County, Utah, USA, where it occurs as sprays and subparallel groups of yellow blades in a secondary assemblage with ammoniozippeite, blödite, boussingaultite, gypsum, hexahydrite, kröhnkite, plášilite and quartz. The streak is very pale yellow. Crystals are transparent with vitreous lustre. The tenacity is brittle, the Mohs hardness is ∼2½, the fracture is curved. The mineral is soluble in H 2 O and has a measured density of 3.06(2) g·cm –3 . The mineral is optically biaxial (+) with α = 1.560(2), β = 1.564(2), γ = 1.589(2); 2V = 43(1)°; orientation: X = a , Y = b , Z = c ; pleochroism: X colourless, Y yellow, Z yellow; X < Y ≈ Z . Electron microprobe analyses provided [(NH 4 ) 1.895 Na 0.065 K 0.040 ] Σ2.000 (Mg 0.755 Mn 0.252 ) Σ1.007 (U 0.996 O 2 ) 2 (S 1.002 O 4 ) 4 (H 1.998 O) 8 . Svornostite-(NH 4 ) is orthorhombic, Pmn 2 1 , a = 13.0259(9), b = 8.2909(4), c = 11.2589(4) Å, V = 1215.92(11) Å 3 and Z = 2. The crystal structure ( R 1 = 0.0243 for 2222 I > 2σ I reflections) contains uranyl-sulfate chains that are linked into sheets by MgO 2 (H 2 O) 4 octahedra and 9- and 10-coordinated NH 4 + groups. The sheet has the same topology as the sheets in several synthetic uranyl selenates. Svornostite-(NH 4 ) is a member of the newly established svornostite group, which also includes svornostite-(K), oldsite-(K), rietveldite and zincorietveldite.

The geologic history of dissolved silica concentration in the ocean (DSi) is central to understanding the evolution of silica biomineralization, the interactions between the global carbon and silicon cycles, and their combined role controlling global climate over geologic time. However, the silica cycle in the geologic past is under-constrained, especially during major mass extinction events that impacted biosilicifiers and were associated with dramatic climate change. We measured the silicon isotope ratios (δ30Si) of 76 sponge spicules from the Panthalassic Ocean spanning the Triassic–Jurassic boundary (ca. 201 Ma) to constrain DSi concentrations during the mid-Mesozoic. Spicule measurements have mean δ30Si values of –0.25‰ ± 0.99‰. Our data, combined with constraints on seawater δ30Si from coeval radiolarians, suggest that mid-Mesozoic DSi was between 20–100 µM, a similar range to the modern ocean. Our results support increasing evidence that by the Mesozoic DSi had already decreased by orders of magnitude relative to the Precambrian. These results imply that radiolarians and sponges were drawing down DSi prior to diatom ecological dominance. Increasing sponge δ30Si values across the Triassic–Jurassic boundary, coupled with modeling evidence and previous palaeoecological observations, support that warming, increased weathering, and Si delivery before the end-Triassic extinction may have facilitated sponge expansion during the extinction recovery interval.

Whole microorganisms are rarely preserved in the fossil record but actively silicifying environments like hot springs provide an opportunity for microbial preservation, making silicifying environments critical for the study of microbial life through time on Earth and possibly other planetary bodies. Yet, the changes that biosignatures may undergo through lithification and burial remain unconstrained. At Steep Cone Geyser in Yellowstone National Park, we collected microbial material from (1) the living system across the active outflows, (2) the silicified areas adjacent to flows, and (3) lithified and buried material to assess the preservation of biosignatures and their changes across the lithification transect. Five biofabrics, built predominantly by Cyanobacteria Geitlerinema, Pseudanabaenaceae, and Leptolyngbya with some filamentous anoxygenic phototrophs contributions, were identified and tracked from the living system through the process of silicification/lithification. In the living systems, δ30Si values decrease from +0.13‰ in surficial waters to -2‰ in biomat samples, indicating a kinetic isotope effect potentially induced by increased association with actively growing biofabrics. The fatty acids C16:1 and iso-C14:0 and the hydrocarbon C17:0 were disentangled from confounding signals and determined to be reliable lipid biosignatures for living biofabric builders and tenant microorganisms. Builder and tenant microbial biosignatures were linked to specific Cyanobacteria, anoxygenic phototrophs, and heterotrophs, which are prominent members of the living communities. Upon lithification and burial, silicon isotopes of silicified biomass began to re-equilibrate, increasing from δ30Si -2‰ in living biomats to -0.55‰ in lithified samples. Active endolithic microbial communities were identified in lithified samples and were dominated by Cyanobacteria, heterotrophic bacteria, and fungi. Results indicate that distinct microbial communities build and inhabit silicified biofabrics through time and that microbial biosignatures shift over the course of lithification. These findings improve our understanding of how microbial communities silicify, the biomarkers they retain, and transitionary impacts that may occur through lithification and burial.

The selective separation of ions from aqueous systems, and even in the human body, is a crucial to overall environmental management and health. Nanoporous materials are widely known for their selective removal of cations from aqueous media, and therefore have been targeted for use as a pharmaceutical to treat hyperkalemia. This study investigated the detailed crystallographic molecular mechanisms that control the potassium ion selectivity in the nanoporous cubic zirconium silicate (CZS) related materials. Using time-resolved in situ Raman spectroscopy and time-resolved in situ X-ray diffraction, the selectivity mechanisms were determined to involve a synchronous cation-cation repulsion process that serves to open a favorable coordination bonding environment for potassium, not unlike the ion selectivity filter process found in potassium ion channels in proteins. Enhancement of ion exchange was observed when the CZS material was in a partial protonated state (≈3:1 Na:H), causing an expansion of the unit-cell volume, enlargement of the 7 member-ring window, and distortion of framework polyhedra, which allowed increased accessibility to the cage structures and resulted in rapid irreversible potassium ion exchange.

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Ooids (calcium carbonate coated grains) are common in carbonate environments throughout geologic time, but the mechanism by which they form remains unclear. In particular, the rate of ooid growth remains elusive in all but a few modern marine environments. In order to investigate the rate of ooid growth in a non-marine setting, we used 14C to date ooids from Great Salt Lake, Utah, a well-known site of aragonitic ooids. Bulk ooids obtained from the northern shore of Antelope Island and the northeast shore of Great Salt Lake near Spiral Jetty were sieved into different size fractions and produced mean ages ranging between 2728±15 and 4373±20 14C yr BP. Larger ooids were older than smaller ooids, implying that larger ooids grew in the environment for a longer duration, with the caveat that bulk age dating integrates the growth history of an ooid. To better resolve growth history, ooids from the coarse fraction were sequentially dissolved, and 14C ages were obtained for each dissolution step to create a time series of ooid growth. The results of the sequential dating indicate that the coarse Great Salt Lake ooid growth began between 5800-6600 ± 60 14C yr BP while their outer cortices are nearly modern. Sequentially dated ooids from the South Arm of Great Salt Lake at Antelope Island record a nearly linear growth history (~ 10-15 µm/kyr), whereas ooids from Spiral Jetty record somewhat faster growth between ~6000 and 4000 years ago (0.03 – 0.06 µm/yr) followed by a 10x slower growth history for the remainder of their lifespan (0.003 – 0.008 µm/yr). The lifespan of Great Salt Lake aragonitic ooids is two to six times longer than those from modern marine environments, and thus provides a unique end member for understanding the mechanisms behind ooid formation. The ooid age range indicates that geochemical parameters measured from bulk ooid dissolution integrates over ~6000 years and thus does not represent a geochemical snapshot in time, as some previous studies have suggested.

This issue of New Mineral Names provides a summary of the newly described minerals donowensite, mikehow-ardite, bortolanite, fluorsigaiite, alumolukrahnite, ferro-ferri-katophorite, tomsquarryite, and argentotetrahedrite-(Zn).

In this issueThis issue of New Mineral Names provides a summary of new species that contain arsenic and lead. As of November 2022, there are 1219 minerals that contain constituent arsenic or lead, which is roughly 20% of all known mineral species. These two elements are an important component in many of the newly described minerals that typically form from hydrothermal or other diagenetic processes. Here we look at nitroplumbite, thorasphite, tennantite-(Cd), paradimorphite, tombstoneite, aldomarinoite, lomardoite, dobšináite, panskyite, yugensonite, and kufahrite.

This issue of New Mineral Names summarizes new species that contain toxic heavy metals and rare earth elements with a partial focus on new minerals found in China. All these new minerals have potential uses for environmental and technological applications, and their origins reflect historical mining or cultural significance. Here we look at fluorbritholite-(Nd), napoliite, scenicite, evseeite, haitaite-(La), dongchuanite, liguowuite, and gysinite-(La).