Ferrite Layer Research Articles

Reverse-Bent Modular Coil Structure with Enhanced Output Stability in DWPT for Arbitrary Linear Transport Systems

Dynamic wireless power transfer (DWPT) systems with segmented transmitters suffer from output pulsations during the moving process. Although numerous coil structures have been developed to mitigate this fluctuation, the parameter design process is complicated and restricted by specific working conditions (e.g., air gaps). To solve these problems, a novel reverse-bent modular transmitter structure is proposed for DWPT in industrial automatic application scenarios such as linear transport systems. Considering the heterogeneous current density distribution in the adjacent region between two coils which causes a drop in magnetic field, the proposed coil structure attempts to eliminate the effects of the adjacent region by bending the terminal parts of each coil reversely to the ferrite layer for shielding. Compared to traditional planar couplers, this structure array can generate a uniform magnetic field over various air gaps. A 100 W laboratory prototype was built to verify the feasibility of the proposed system. The experimental results show that the proposed system achieved a constant output voltage, and the output pulsation was within ±2.3% in the dynamic powering process. The average efficiency was about 88.29%, with a 200 mm transfer distance. When the air gap varied from 20 mm to 30 mm, the system could still retain constant voltage output characteristics.

Tensile and cracking behavior of thin-walled 316Ti austenitic steel after exposure to 550 °C lead-bismuth eutectic with different oxygen concentration

The corrosion evolution of 316Ti steel in 550°C lead-bismuth eutectic (LBE) with oxygen concentrations (Co) of 5×10-6 wt.% and 5×10-8 wt.% and their impact on the tensile behavior were investigated in this study. The steel primarily underwent oxidation at Co of 5×10-6 wt.%, slightly influencing the tensile strength and elongation of specimen within 1000 hours exposure. In contrast, the structural integrity and tensile strength of specimen were significantly deteriorated at Co of 5×10-8 wt.% where the steel mainly experienced dissolution corrosion. The cracking behaviors of oxide layer and ferrite layer, and their influences on the failure of thin-walled specimen were discussed. Special concerns should be raised on the detrimental effect of localized corrosion, such as intergranular oxidation, LBE-wetted precipitate bands and dissolution pits, since cracks are expected to initiate easily in these zones and propagate into steel matrix under tension, potentially leading to the premature failure of thin-walled components.

Two-Stage Optimal Design of Concentric Ferrite PM Layer IPMSM for Micro-EV Traction Considering Driving Characteristics

Two-Stage Optimal Design of Concentric Ferrite PM Layer IPMSM for Micro-EV Traction Considering Driving Characteristics

Hybrid Aerosol Jet Printing and Electrodeposition of Ferrite-Sandwiched Inductors

The additive manufacturing (AM) of inductors of suitable size to be integrated into packaged electronics is attractive to customize the device characteristics for the specific application. Magnetic ferrite cores are widely used in conventional inductors, however, wire wound inductors can be brittle, heavy, bulky. Planar spiral inductors in a sandwich configuration present a promising alternative. Aerosol jet printing, a direct write AM technology, can deposit metal inks at a resolution of < 10 µm. Metal nanoparticle inks have limited conductivity at < 40% bulk. Building a higher profile may result in loss of resolution. Electrodeposition offers the ability to plate thick layers of highly conductive metals, including copper and nickel which are normally hard to access as nanoparticle inks compatible with aerosol jetting. We have previously shown the construction of a multi-layer flyback transformer with this hybrid aerosol jet and electrodeposition method. [1]We present a three-layer planar inductor with the first layer being a 1.3mm stack of ferrite sheets (Fair-Rite) with a 9 mm x 9 mm footprint integrated onto a circuit board. The intermediate layer consists of a spiral inductor made by aerosol jet printing UTDots Ag40X silver nanoparticle ink as the seed layer. To achieve high accuracy, the inductor was printed with a rotary axis stage. Electrodeposition in an acidic CuSO4 plating bath on top of the Ag seed layer resulted in thicknesses of 50 µm. A submicron layer of Ni is added for oxidation protection by electrodeposition from a Ni-Sulfamate bath. Lastly, a top 1.3 mm ferrite stack, with laser cut holes, is added to provide pass throughs for wire bonding. Figure 1 shows a micrograph of an inductor as printed, after electrodeposition, and with the top ferrite layer. Electrical measurements including impedance characteristics will be presented.SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525. The SAND No. is SAND2023-14571A.Figure 1. Construction of a ferrite-sandwiched inductor with (a) the aerosol jet printing of an Ag seed layer, (b) after electroplating of Cu and Ni.

Dynamic transition of internal oxides during high dew point heat treatment in Fe-2.4Mn-0.4Si-0.13C alloy

The origin of the dynamic transition of internal oxides was clarified in Fe‐2.4Mn‐0.4Si‐0.13C‐based steel during decarburization annealing at 1073 K. High dew point with H2 gas leads to the formation of deep decarburized ferrite layers containing grain boundary internal oxides. Microstructural characterization reveals the oxide transition from Mn2SiO4 to α-SiO2 at the tip of the internal oxidation layer and from α-SiO2 to Mn2SiO4 at the middle range of the internal oxidation layer. The dynamic transition between Mn2SiO4 and α-SiO2 is understood by the depletion in Mn contents and change of oxygen content, which change the normalized driving force of both oxides. The study gives a detailed mechanism of internal oxide formation and growth in multi-phase steel during high dew point annealing. Impact statementDuring high dew-point decarburization annealing, the fluctuation of Mn contents affects the driving force to form an internal oxide, resulting in the dynamic transition between Mn2SiO4 and α-SiO2.

Synthesis of New Complex Ferrite Li0.5MnFe1.5O4: Chemical-Physical and Electrophysical Research.

In this article, the sol-gel method was used as a synthesis method, which shows the physicochemical nature of the synthesis of a new complex material, ferrite Li0.5MnFe1.5O4. The structure and composition of the synthesized ferrite were determined by X-ray phase analysis. According to analysis indicators, it was found that our compound is a single-phase, spinel-structured, and syngony-cubic type of compound. The microstructure of the compound and the quantitative composition of the elements contained within it were analyzed under a scanning electron microscope (SEM). Under a scanning electron microscope, microsystems were taken from different parts of Li0.5MnFe1.5O4-type crystallite; the elemental composition of crystals was analyzed; and the general type of surface layer of complex ferrite was shown. As a result, given the fact that the compound consists of a single phase, the clarity of its construction was determined by the topography and chemical composition of the compound. As a result, it was found that the newly synthesized complex ferrites correspond to the formula Li0.5MnFe1.5O4. The particles of the formed compounds have a large size (between 50.0 μm or 20.0 μm and 10.0 μm). Electrophysical measurements were carried out on an LCR-800 unit at intervals of 293-483 K and at frequencies of 1.5 and 10 kHz. An increase in frequency to 10 kHz led to a decrease in the value ε in the range of the studied temperature (293-483 K).

Ontology‐Based Data Acquisition, Refinement, and Utilization in the Development of a Multilayer Ferrite Inductor

A key aspect in the development of multilayer inductors is the magnetic permeability of the ferrite layers. Herein, the effects of different processing steps on the permeability of a NiCuZn ferrite are investigated. Dry‐pressed, tape‐cast, and cofired multilayer samples are analyzed. An automated data pipeline is applied to structure the acquired experimental data according to a domain ontology based on Platform MaterialDigital core ontology. Example queries to the ontology show how the determined process–property correlations are accessible to nonexperts and thus how suitable data for component design can be identified. It is demonstrated how the inductance of cofired multilayer inductors is reliably predicted by simulations if the appropriate input data corresponding to the manufacturing process is used.

Synthesis and physico –chemical characteristics of complex ferriteCrNaFe2O5

The article discusses for the first time the synthesis, radiographic and electron microscopic examination of CrNaFe2O5, synthesized using the high – temperature Sol-gel method. The phase of complex ferrites was synthesized using Sol-Gel synthesis method at high temperature. Initially, the structure of CrNaFe2O5 composite ferrite was researched by X-ray phase analysis and SEM, the syngony type, elementary cell parameters, radiographic and pycnometric densities and elemental analysis were defined: CrNaFe2O5 -а=5.0289, в= 5.0289, с=13.6938 Å , ρx-ray.= 5.327 g/sm3 , ρpycn.=5.331 g/sm3. A comparative analysis of the connection between the parameters of the Crystal cell of the initial materials and of the obtained complex ferrites was carried out. Through a scanning electron microscope, microsystems were taken from different parts of CrNaFe2O5 type crystallite, the elemental composition of crystals was analyzed, and the general type of surface layer of complex ferrite was displayed. As a result, the fact that the compound consists of a single phase, the clarity of its construction was determined by the topography and chemical composition of the compound. Consequently, it was discovered that the newly synthesized complex ferrites correspond to the formula CrNaFe2O5. The particles of the formed compounds have a large size (between 200 µm, 20.0 µm and 5 µm). The results of the element analysis show that the compound is compatible.

Zinc Ferrite Nanoparticle Coatings on Austenitic Alloy Steel.

The phase transition of austenitic stainless steel of commercial label CL20ES and zinc ferrite nanoparticles was studied in an oxidative atmosphere of dry air to develop a low-cost, effective technique for covering-layer fabrication. CL20ES powder and zinc ferrite powder were mechanically mixed. This mixture was studied in an atmosphere of dry air at different annealing temperatures from room temperature to 900 °C. The employed characterization techniques are X-ray powder diffraction, Mössbauer spectroscopy in the transmission geometry, and scanning electron microscopy with elemental mapping. The fabricated layers were also characterized by surface-specific techniques such as conversion electron Mössbauer spectroscopy and grazing incidence X-ray powder diffraction. The analyzed powder mixture shows resistance against oxidation in dry air and high temperatures. These results were employed to produce zinc ferrite covering layers on 3D-printed cylinders of CL20ES. The results show a predisposition of zinc ferrite to be recrystallized at temperatures above 350 °C without the production of corrosive substances on steel. The zinc ferrite layers were analyzed by an ultrasonic hardness tester as well, which proved the hardness enhancement.

Optimizing the Strength and Toughness of V/Mo-Modified 0.22C-5.24Mn Steel by Short-Time Partial Austenitization Process.

In order to obtain the good match between yield strength and low-temperature toughness, the short-time partial austenitization (SPA) process was employed for V/Mo-bearing 0.22C-5.24Mn steel. The initial microstructure after intercritical tempering was dual-phase ferrite and reversed austenite (RA), while the final microstructure consisted of ferrite, RA, and secondary martensite (SM) after being subjected to the SPA process. (V, Mo)C with disclike morphology mainly precipitated during intercritical tempering, and the aspect ratio of particles decreased, leading to the appearance of near-spherical morphology. After being subjected to SPA process, the resultant multiphase hierarchical microstructure (three layers: outer layer of ferrite, interlayer of SM, and inner layer of RA) enabled a high yield strength of 1097 MPa, a total elongation of 14%, and an impressive impact energy of 33.3 J at -20 °C. The strengthening contribution of (V, Mo)C precipitation was estimated to be about 108 MPa.

Transverse electric guided modes in metal-LHM-ferrite slab waveguide structures

Transverse electric guided modes in metal-LHM-ferrite slab waveguide structures

Thermally stressed state of the layer under the influence of currents periodic with respect to the longitudinal coordinate

To evaluate the impact of the important non-uniformity technological factor of the external electric current distribution on the low-temperature heating parameters of flat ferrite elements, taking into account the stressed state (strength characteristics), a model problem is considered to determine and study the thermomechanical behavior of the ferrite layer under the influence of a quasi-steady electromagnetic field created by the current flowing in the current-carrying plane, the density of which changes sinusoidally along the longitudinal coordinate. In accordance with the earlier results regarding the dependence of the heating process on the frequency of external electromagnetic influence, it is accepted that the circular carrier frequency of the electromagnetic field is outside the vicinity of the resonant ones (when the thermally stressed state has an almost quasi-static character). In this case, the calculation scheme consists of three stages for sequentially determining the parameters that describe the electromagnetic, temperature, and mechanical fields.

NATURAL ELECTROMAGNETIC MODES OF A COMPOSITE OPEN STRUCTURE INVOLVING A PERFECTLY CONDUCTING STRIP GRATING, AN INHOMOGENEOUS FERRITE LAYER, AND A MONOLAYER OF GRAPHENE

Subject and Purpose. Сonsidered are the natural modes and their correspondent eigenfrequencies of a composite structure which is nonuniform along one of the coordinates and consists of a lossy ferromagnetic layer placed in a static magnetic field. The layer involves a perfectly conducting strip grating at one of its boundaries and a graphene monolayer at the other. Methods and Methodology. The above stated problem can be approached within the analytical regularization procedure developed for dual series equations. The latter concern a broad class of diffraction problems which include, in particular, the diffraction of monochromatic plane waves on strip gratings placed at the boundary of a gyromagnetic medium. The amplitudes of the electromagnetic eigenmodes can be obtained from the infinite set of homogeneous linear algebraic equations solvable within a truncation technique. The roots of the system’s determinant represent complex-valued eigenfrequencies of the system under investigation. The material parameters adopted in our computations for the ferromagnetic layer correspond to such of yttrium iron garnet. Results. A number of numerical programs have been developed which permit analyzing the dependences of wave field eigenfunctions and complex eigenfrequencies upon geometrical parameters of the structure (such as grating slot width and period, and thickness of the lossy layer), as well as on electrodynamic parameters of the ferromagnet and graphene characteristics, specifically the chemical potential and relaxation energy of electrons. A number of behavioral regularities have been established, as well as the effect of non-uniformity of ferrite layer parameters upon the structure’s eigenfrequencies and wave field eigenfunctions. Conclusions. The structure under study has been shown to be is an open oscillatory system with a set of complex-valued natural frequencies demonstrating finite points of accumulation. The real parts of these eigenfrequencies lie in a certain interval determined by characteristic frequencies of the ferrite layer, while the imaginary parts are negative, such that the correspondent natural modes show an exponential decay with time. The grating edges represent the mirrors which the natural surface oscillations are reflected from, being supported at that by the ferromagnetic medium. The results obtained in this paper can be useful for creating the elemental base for microwave devices and the devices themselves.

Soft magnetic composite of Ni3Fe/ZnFe2O4 type obtained by mechanical alloying/milling and spark plasma sintering

Soft magnetic composite powder of Ni3Fe/ZnFe2O4 type has been obtained by mechanical milling of nanocrystalline Permalloy (Ni3Fe) particles with ZnFe2O4 particles. The nanocrystalline Ni3Fe particles were synthesised by mechanical alloying of elemental Ni and Fe powder. During the milling time, some of the ZnFe2O4 particles are embedded on the surface, and others are encapsulated in the volume of the Permalloy particles, creating a „raisin-bread” like structure. Also, at the surface of the Ni3Fe particles, a quasi-continuous layer of zinc ferrite is formed. The as formed composite particles have a structure of pseudo core-shell type, with a “raisin-bread” core. Upon mechanical milling, the phases are preserved according to X-ray diffraction (XRD) investigations, although the system magnetisation presents a slight decrease. The densification of the composite powder has been carried out using spark plasma sintering (SPS) technique at a sintering temperature range of 500–700 °C without holding time. The density and the electrical resistivity of the samples increase upon increasing the sintering temperature. Higher magnetisation is obtained for the sample sintered at 700 °C and accompanied by a lower coercive field. Upon sintering, a reaction at interface, between the Ni-based alloy and zinc ferrite occurs, leading to the formation of a new phase. The testing of the toroidal-shaped magnetic composite in the alternative current regime shows that the best results are obtained on the sample sintered at 700 °C. The losses decomposition was performed and showed that the dynamic losses become predominant after 1 kHz. The samples have been investigated by X-ray diffraction, scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), vibrating sample magnetometer (VSM) for powder samples and by DC and AC magnetic investigation by hysteresisgraph method and electrical resistivity investigations for the sintered compacts.

Nano-lithium ferrite/nanosilica-filled butadiene-acrylonitrile rubber for microwave absorption

Recently, the development of flexible and lightweight microwave-absorbing materials has become a trendy topic. Hence, the principal aim of this work is to enhance the microwave-absorbing performance of butadiene-acrylonitrile rubber (NBR) by incorporating novel reinforcing nanofillers. Cost-effective nano-lithium ferrite/nanosilica is synthesized via the precipitation of two thin layers of lithium ferrite with thicknesses of 10 and 20 % on the surface of cheap nanosilica extracted from rice husk agro-waste. To achieve optimal microwave-absorbing performance, both LiFe 10 %/Si and LiFe 20 %/Si NPs were incorporated into the NBR matrix at various loadings (2, 4, 8, and 16 parts per hundred rubber (phr)). Several investigations were performed on the NBR nanocomposites to explore their morphology, curing behavior, mechanical, equilibrium swelling, magnetic properties, and microwave-absorbing behavior. The mechanical characteristics of NBR nanocomposites reveal that the inclusion of LiFe/Si NPs enhanced their modulus, tensile strength, and elongation at break while reducing their hardness. Moreover, the obtained findings clarify that the 16 phr (LiFe 20 %/Si) filled-NBR nanocomposite has superior microwave-absorbing performance with a maximum absorption bandwidth of 2.2 GHz. Overall results reveal that the novel lithium ferrite/silica nanoparticles could be an effective filler for enhancing the microwave absorption efficiency of NBR nanocomposites. Thus, this research suggests a novel viewpoint on the fabrication of flexible microwave-absorbing materials.

Ferritic layers formation mechanism during oxidation of FeMnSiCrNi alloys: Effect of temperature and influence on oxidation behavior

Ferritic layer formation occurs after oxidation in Mn-rich austenitic alloys. It has significant effects on high-temperature oxidation resistance, but a better understanding of its formation is needed to control these effects. Thus, two FeMnSiCrNi alloys were exposed to six temperatures between 675 and 800 °C for 100 h. A relationship between mass variation and ferrite thickness was revealed, as Mn and Cr depletion occurred due to the Mn2O3/MnCr2O4 formation. Thermodynamic calculated phase diagrams indicated ferrite stability at high temperatures, affecting oxidation resistance. Finally, the Mn concentration profile changes during oxidation were studied with DICTRA analyses to explain the ferritic layer growth. By describing the growth and characteristics of this layer, the study can serve as a starting point for future investigations into designing more oxidation-resistant FeMnSiCrNi alloys.

Magnetic Coupling Mechanism With Omnidirectional Magnetic Shielding for Wireless Power Transfer

Electromagnetic field is used as medium for wireless power transfer to realize noncontact power transmission, which is hoped to be concentrated in the power transmission channel as much as possible to improve performance and reduce the impact on surrounding environment. A magnetic coupling mechanism (MCM) with omnidirectional magnetic shielding (ODMS) is designed in this article. Ferrite shielding layers are added at the back of power channel to guide more for power transmission and restraint leakage. The reverse-wound magnetic shielding coil and forward-wound power transmitting coil are connected in reverse series to form a bidirectional antiparallel coil, which eliminates the complex control and additional excitation source, and restrict magnetic in the side areas of power channel. Active and passive shielding methods are comprehensively used to improve the magnetic field distribution in the power transmission channel and reduce magnetic in the full space around MCM. The optimal design method of ODMS MCM is summarized, and the experiments are carried out. The results are consistent with the theoretical and simulation analysis. The proposed ODMS MCM can effectively limit magnetic leakage in all directions and improve transmission power and efficiency.

Excitation of exchange spin waves in the transition layer of the two-layer ferrite-ferrite structure

The possibility of intense excitation of exchange spin waves in a tangentially magnetized two-layer epitaxial film of iron yttrium garnet is demonstrated. The waves are excited in a thin transition layer at the interface between the ferrite layers, propagate into the doped layer with reduced magnetization, and reflect from its opposite surface. In continuous excitation mode, they can be observed as a series of spin wave resonance peaks. Mathematical processing of the measured frequencies of resonance peaks allows for the calculation of the magnetization profile of the doped layer and the modeling of the excitation and propagation processes of exchange spin waves. The proposed methodology of mathematical processing can be applied for non-destructive control of the layered structure of epitaxial ferrite structures.

Quantifying Diffusion Across Solid-Solid Interfaces in Electrochemical Cells

Enabling an increased rollout of hydrogen-based technologies requires decarbonisation of both hydrogen production and conversion. Solid Oxide Cells (SOCs), in the form of electrolysers and fuel cells, could play a significant role in achieving this, however lifetime and degradation of SOCs remain major obstacles to commercialisation. Understanding the mechanisms governing ionic transport in ceramics is important to improving the performance and durability of SOCs. Properties such as the oxygen tracer diffusivity, , can be measured by Isotopic Exchange Depth Profiling (IEDP) as developed by Kilner et al. [1].This method has, so far, primarily been used to characterise the properties of single materials; however, SOCs are multilayer devices with solid-solid interfaces that may also affect transport. Some investigations into the diffusion behaviour across multiple layers using the IEDP technique have been done in thin film samples [2][3]. Profiles obtained from these studies appear to show an abrupt concentration drop at the interface between certain materials, indicating an interface which significantly impacts the diffusion behaviour (and by extension the overall cell performance). However, no attempt was made to quantify this interface effect with a theoretical modelling approach.A finite-difference model for diffusion in a system containing multiple layers with interfaces is developed. It numerically solves Fick’s second law of diffusion with various boundary conditions. This model can be used to fit experimental data obtained from tracer diffusion SIMS data, yielding new way of quantifying interfacial resistance. A new interfacial resistance parameter, , has been defined, which quantifies the magnitude of concentration drop across any given interface and thus offers a universal way of numerically characterising resistance to diffusion.The validity of the developed method has been experimentally tested in samples containing layers of lanthanum strontium cobalt ferrite (LSCF) and gadolinium-doped ceria (GDC), a commonly used system in SOCs. Initial data from tracer diffusion experiments as seen in Figure 1 have shown the presence of a significant concentration drop at the interface of a LSCF-GDC stack which can be fitted to the numerical model developed by the authors. This approach is used to measure the changing interface properties under various ageing conditions, as well as the influence of interlayers and material selection on the interfacial resistances both in SOC and other diffusion systems.[1] J. A. Kilner, B. C. H. Steele, and L. Ilkov. Oxygen self-dffusion studies using negative-ion secondary ion mass-spectrometry (sims). Solid State Ionics, 12(MAR):89-97, 1984.[2] K. Develos-Bagarinao, H. Yokokawa, H. Kishimoto, T. Ishiyama, K. Yamaji, and T. Horita. Elucidating the origin of oxide ion blocking effects at gdc/srzr(y)o-3/ysz interfaces. Journal of Materials Chemistry A, 5(18):8733-8743, 2017.[3] Katherine Develos-Bagarinao, Haruo Kishimoto, Jeffrey De Vero, Katsuhiko Yamaji, and Teruhisa Horita. Effect of la0.6sr0.4co0.2fe0.8o3-delta microstructure on oxygen surface exchange kinetics. Solid State Ionics, 288:6-9, 2016.Fig. 1. Oxygen isotopic fraction data of an LSCF layer deposited on a GDC substrate and annealed in Oxygen-18 atmosphere at 650 C for 1h obtained using cross-sectional SIMS (left) and fit of the data using the multi-layer diffusion model developed by the authors (right). Figure 1

Critical raw materials associated with the lateritic bauxite and red mud in West Kalimantan, Indonesia

The Western Indonesia Bauxite Province in Kalimantan is a lateritic bauxite region with a complex history and poorly known sustainable metal contents within the bauxite residue. Bauxite residue produced using the Bayer process contains, notably, scandium. We present new geochemical, mineralogical and geological data from the lateritic bauxite and red mud from the active mine and deposit, which allow us to investigate the behaviour of critical elements during weathering. The geochemical analysis and translated isocon results have shown that the content of scandium in red mud is higher than the average concentration of crustal rocks and is concentrated in the ferrite layer and bauxite residue. A positive correlation between the existence of iron oxyhydroxide mineral in the residual iron-rich layer and red muds with the rare earth elements (REEs) and scandium concentrations may be interpreted as a scavenging effect of mobile REEs. The weathering and leaching processes in bauxite allows the adsorption of the trivalent scandium cation (Sc 3+ ) on goethite and are followed by ionic substitution with other trivalent cations in crystals of hematite. The study illustrates the importance of understanding processes during weathering and laterization for geochemical processes and REE exploration in tropical areas. Supplementary material: Material A, (A) Mineralogical profile of the bauxite, ferrite, and tonalite in Tayan and Mempawah, (B) Ternary diagram of bauxite and their parent rocks, (C) Trace element ratios in bauxite; Material B, Spearman's correlation rank of bauxite and associated rocks from Tayan mine ( n = 35); Material C, (A) XRD patterns of representative samples from the Tayan mine and Mempawah deposit, West Kalimantan, (B) Typical normal (left) and continuum (right) removed reflectance spectral curves of samples are available at https://doi.org/10.6084/m9.figshare.c.6689139 Thematic collection: This article is part of the Geochemical processes related to mined, milled, or natural metal deposits collection available at: https://www.lyellcollection.org/topic/collections/geochemical-processes-related-to-mined-milled-or-natural-metal-deposits