Gavyn Rollinson

University of Exeter | UoE · Department of Camborne School of Mines

Cobalt is mainly produced globally from Cu-Co sediment-hosted deposits in the Democratic Republic of Congo. As mining operations progress, oxidic supergene mineralisation gradually depletes, and many have been or are shifting towards extracting sulphide ore at depth. Overall, copper recovery is consistently higher than cobalt, but no in-depth inves...

The Tellus stream sediment and deep soil geochemistry data sets for Northern Ireland were used to locate four types of critical metals anomalies in granite bedrocks of the Mourne Mountains. A curvi-linear array of Nb, REE, Th and U soil anomalies across the eastern Mourne Mountains correlated with late-stage and eutectic temperature minerals in the...

Porphyry-type deposits are a vital source of green technology metals such as copper and molybdenum. They typically form in subduction-related settings from large, long-lived magmatic systems. The most widely accepted model for their formation requires that mantle-derived magmas undergo an increase in volatiles and ore-forming constituents in mid- t...

Determining the physical and chemical properties of airborne dusts in occupational settings is essential for assessing their potential toxicity as well as the effectiveness of respiratory protective equipment and dust mitigation measures. Here, we report the first successful QEMSCAN® automated mineralogical analysis of potentially toxic PM4 and PM2...

The European cross-border Project MARINEFF explores the use of eco-friendly concrete materials in the construction of marine structures (oyster bed modules, dykes, boat moorings and rockpools). The structures and materials are designed to protect and improve the local biodiversity of the marine environment of the Channel / La Manche. This paper foc...

Combined mineralogical and chemical study of coal mine gangues from Poland, to assess their utility as concrete aggregates.

The early rejection of gangue minerals, at coarse ore particles size (preconcentration), has been shown to be a viable option to cost reduction in many mineral processing applications. A promising technique being explored for efficient ore preconcentration is the Near InfraRed (NIR) spectroscopy. This paper attempts to validate the efficiency of ne...

How and why magmatic systems reactivate and evolve is a critical question for monitoring and hazard mitigation efforts during initial response and ongoing volcanic crisis management. Here we report the first integrated petrological results and interpretation provided to monitoring authorities during the ongoing eruption of Cumbre Vieja, La Palma, C...

Cobalt (Co) mine production primarily originates from the sediment-hosted copper (Cu) deposits of the Democratic Republic of Congo (DRC). These deposits usually consist of three ore zones with a supergene oxide ore blanket overlying a transition zone which grades into a sulphide zone at depth. Each of these zones display a mineral assemblage with v...

The first products of the current Cumbre Vieja eruption comprise simultaneous tephra fall from near-continuous, gas-rich eruption plumes and lava flows. From combined field, petrographic and geochemical analyses we identify: low percentage mantle melts with a variably-equilibrated multimineralic crystal-cargo and compositional fractionation by erup...

Porphyry-type deposits are the world’s main source of copper and molybdenum and provide a large proportion of gold and other metals. However, the mechanism by which mineralising fluids are extracted from source magmas and transported upwards into the ore-forming environment is not clearly understood. Here we use field, micro-textural and geochemica...

Platinum-group elements (PGE) display a chalcophile behaviour and are largely hosted by base metal sulphide (BMS) minerals in the mantle. During partial melting of the mantle, BMS release their metal budget into the magma generated. The fertility of magma sources is a key component of the mineralisation potential of large igneous provinces (LIP) an...

The Tuntsa Suite is a polymetamorphic Archean complex mainly consisting of metasedimentary gneisses. At least two strong metamorphic events can be distinguished in the area. The first took place at high temperatures in the Neoarchean at around 2.70–2.64 Ga, indicated by migmatisation and U-Pb ages of metamorphic zircon. During the Paleoproterozoic,...

Rare earth element (REE)-bearing carbonatite deposits commonly contain a wide range of different REE-and REE-bearing minerals associated with various gangue matrices. In order to select the most-suitable mineral processing technique for these deposits, it is essential to identify and quantify the minerals of interest, including their liberation, as...

The geological mapping carried out by William Smith, which resulted in the publication of his famous map in 1815, was remarkable in many respects, not least because it relied on him being able to make consistent and accurate observations on the rock types he encountered during his fieldwork. This ability, gained from his many years studying rocks,...

As part of a study investigating the influence of mineralogical variability in a sediment hosted copper–cobalt deposit in the Democratic Republic of Congo on flotation performance, the flotation of nine sulphide ore samples was investigated through laboratory batch kinetics tests and quantitative mineral analyses. Using a range of ore samples from...

An imported flanged rimsherd discovered on the early medieval site of Kilree 3, Ireland: a study in archaeological deposition and provenance using automated SEM-EDS analysis (QEMSCAN)

Following a regional reconnaissance stream sediment survey that was carried out in the northern Vosges Mountains in 1983, a total of 20 stream sediment samples were collected with the aim of assessing the regional prospectivity for the granite-hosted base and rare metal mineralisation of the northern Vosges magmatic suite near Schirmeck. A particul...

Automated mineralogy by computer controlled SEM-EDS is an analysis technique used dominantly in the Geosciences, to obtain mineralogical and textural data at the micron scale (by mineral mapping). It is a specialist technique that focuses on solid samples and especially minerals, rocks or soil. It is able to provide large, precise and repeatable da...

The Weaklaw vent in SE Scotland (East Lothian coast), inferred to be Namurian, produced lava spatter and volcanic bombs. The latter commonly contained ultramafic xenoliths. All were metasomatised by carbonic fluids rich in incompatible elements. The lavas and xenoliths are inferred to have been basanites and lherzolites prior to metasomatism. The a...

Automated Scanning Electron Microscopy (ASEM) systems are applied in the mining industry to quantify the mineralogy of the ore feed and products. With society pushing towards sustainable mining, this quantification should be comprehensive and include trace minerals since they are often either deleterious or potential by-products. Systems like QEMSC...

The synthesis of manufactured soils converts waste materials to value-added products, alleviating pressures on both waste disposal infrastructure and topsoils. For manufactured soils to be effective media for plant growth, they must retain and store plant-available nutrients, including nitrogen. In this study, biochar applications were tested for t...

Volcanic ash particle properties depend upon their genetic fragmentation processes. Here, we introduce QEMSCAN Particle Mineralogical Analysis (PMA) to quantify the phase distribution in ash samples collected during activity at Santiaguito, Guatemala and assess the fragmentation mechanisms. Volcanic ash from a vulcanian explosion and from a pyrocla...

QEMSCAN phase maps of at 1 and 2 micron step sizes. Grain size distribution curves from laser diffraction particle size analysis

A Red Slip Ware Flanged Bowl discovered in Ireland: an exploration of archaeological deposition and provenance using automated SEM-EDS analysis (QEMSCAN). In M. Duggan ed. Proceedings of the Ceramics and Atlantic Connections Symposium, 26-27 March 2014. Roman and Late Antique Mediterranean Pottery series.

Because of their low grades in critical metals such as Light Rare Earth Elements (LREE) or Sn, rare-metal granites are not considered as economic for metal recovery but, when altered, they are often exploited for their industrial minerals. The St Austell rare-metal granite is well known for its world-class kaolin deposits which formed as a result o...

Loki’s Castle on the Arctic Mid-Ocean Ridge (AMOR) is an area of possible seafloor massive sulphide (SMS)-style mineralisation under Norwegian jurisdiction, which, due to mounting social pressure, may be a strategic future source of base and precious metals. The purpose of this study is to characterise mineralised material from a hydrothermal vent...

Artificial soils made from waste materials offer an alternative to imported natural topsoils, notably in large-scale groundwork and reclamation projects. Benefits include diversion of waste from landfill and recycling. Nonetheless, there is limited information on the characteristics needed to support plant growth in the long term, particularly the...

Although cobalt mineralisation has been noted in Cornwall and Devon in the mining literature, there are limited details of its production and paragenesis; detailed mineral studies of cobalt are almost non-existent. This paper describes in detail previously unrecorded cobalt mineralisation discovered at Porthtowan, Cornwall, in the vicinity of old w...

Volcanic ash particle properties depend upon their genetic fragmentation processes. Here, we introduce QEMSCAN particle mineralogical analysis (PMA) to quantify the phase distribution in two ash samples collected during activity at Santiaguito, Guatemala and assess the fingerprint of fragmentation mechanisms. Volcanic ash from a Vulcanian explosion...

Tungsten is considered by the European Union as a critical raw material for future development due to its expected demand and scarcity of resource within Europe. It is therefore, critical to optimize European tungsten operations and maximise recoveries. The role of enhanced gravity/centrifugal concentrators in recovering tungsten from ultra-fine fr...

Abstract: The historic Penouta mine in northwest Spain is the focus of efforts to extract tantalum from tin mining waste. This paper describes the characterisation of the tantalum mineralogy of waste material from the deposit. Characterisation was realised using quantitative mineralogy and geochemistry. This paper further identifies other phases of...

In this contribution, we present the mineralogy and geochemistry of Tabuaço skarn deposit, one of the most important tungsten deposits of the “Douro Scheelite Belt”, Portugal. Tabuaço is a W- (Sn) proximal skarn deposit located at the contact between “Bateiras Formation” from the Schist Greywacke Complex and Tabuaço Granite. The Tabuaço deposit has...

Two occurrences of platinum-group elements (PGEs) along the northern margin of the Skaergaard intrusion include a sulfide-bearing gabbro with slightly less than 1 ppm PGE + Au and a clinopyroxene-actinolite-plagioclase-biotite-ilmenite schist with 16 vol% sulfide and 1.8 ppm PGE + Au. Both have assemblages of pyrrhotite, pentlandite, and chalcopyri...

Beside the Scandinavian countries and Serbia, Portugal is among the European countries with the most significant lithium resources. The Li-rich occurrences in Portugal are mainly associated with aplite-pegmatite dykes and sills intruded in granitic and metasedimentary rocks of the Central Iberian and Galicia – Trás-os-Montes geotectonic zones (Carv...

Internal unpublished study. CSM, UoE, UK

https://authors.elsevier.com/a/1W18A1LQnuHWOC Underlying bedrock is often the source of elevated levels of potentially toxic elements (PTEs) (including Ni and Cr) in soils, which can be at concentrations exceeding regulatory guidelines for the protection of human health. However geogenic contaminants are often not significantly bioavailable to hum...

Dredging activities to extend, deepen and maintain access to harbours generate significant volumes of waste dredged material. Some ways are investigated to add value to these sediments. One solution described here is their use in road construction following treatment with hydraulic binders. This paper presents the characterisation of four sediments...

The mineralogy and texture of a crushed rock aggregate can be established through using a thin section and an optical microscope. However, there are limitations due to the difficulties in recognising and identifying the smallest crystals, many of which may bind the rock together or are alteration products of larger crystals that can have a marked e...

An unworked quartz vein-hosted gold deposit occurs in the Clew bay area of County Mayo, western Ireland. The veins are late-Caledonian in age and transect greenschist-facies poly-deformed Silurian quartzites. The veins contain disseminated arsenopyrite thatmay be a primary mineral source for elevated levels of arsenic (As) found in groundwater samp...

The first ever bulletin of the AMG-MinSoc, with a Special Feature on automated SEM-EDS analysis for non-sulphide Zn-deposits.

The management of dredged marine sediment is an issue for many harbours, particularly when contaminant concentrations prevent disposal at sea. The stabilisation/solidification of the sediments with hydraulic binders for a use in road subgrade layer is a potential alternative solution. However, the environmental acceptability is not yet fully establ...

Santiaguito volcano exhibits cyclic deformation and regular Vulcanian gas-and-ash explosions, ongoing for almost 100 years. Airfall ash samples collected 500 m from the active Caliente vent constitute a snapshot of the ash-forming mechanisms between and during eruptive events. Samples collected following ashfall from Vulcanian explosion plumes and...

A liberation simulation is outlined based on image analysis of mineral texture images such as those produced by automated mineralogical analysis. The method relies on a freeware image analysis programme, Fiji, and uses Voronoi tessellations to represent a fragmentation pattern. This pattern is superimposed onto a mineral texture image and the miner...

The SW England ore region contains significant amounts of indium (In) in Early Permian granite-related skarn and lode parageneses and, to a lesser extent, Triassic epithermal “crosscourse” veins. Ore parageneses that predate granite emplacement (Devonian and Lower Carboniferous sedimentary exhalative and vein parageneses) are largely devoid of In....

A comparison of two contrasting altered megacrystic granites from Trevalgan Farm and Belowda Beacon

Mineralogical analysis was carried out by QEMSCAN using the methodology described by Andersen et al. (in press). Four major mineralogical types were recognised and the key mineralogical characteristics of these types are listed in Table A.1 on the following page. A list of potential minerals included in the QEMSCAN mineral groups is given in Table...

RESUMEN Se estudia la composición por difracción de rayos X y QEMSCAN (19 muestras) de fangolitas y margas de la Formación Vaca Muerta, acumuladas durante la transgresión tithoniana de la Cuenca Neuquina. Se definen importantes variaciones composicionales entre tipos litológicos y facies sedimentarias. Las rocas del sector marginal de la cuenca mue...

Supergene nonsulfide Zn-Pb deposits consist mainly of Zn-Pb carbonates, Zn silicates, Fe hydroxides, and minor Zn-Pb phosphates, commonly associated with remnants of primary sulfides (sphalerite and galena). The relative abundances of these mineral phases are strongly dependent on the type of host rock. Their variable mineralogy is complex to chara...

Trinitite is the glass formed during the first atomic bomb test near Socorro, New Mexico, on July 16, 1945. The protolith for the glass is arkosic sand. The majority of the glass is bottle green in color, but a red variety is found in the northern quadrant of the test site. Glass beads and dumbbells, similar in morphology to micro-tektites, are als...