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Heavy minerals are typically rare but important components of siliciclastic sediments and rocks. Their abundance, proportions, and variability carry valuable information on source rocks, climatic, environmental and transport conditions between source to sink, and diagenetic processes. They are important for practical purposes such as prospecting for mineral resources or the correlation and interpretation of geologic reservoirs. Despite the extensive use of heavy mineral analysis in sedimentary petrography and quite diverse methods for quantifying heavy mineral assemblages, there has never been a systematic comparison of results obtained by different methods and/or operators. This study provides the first interlaboratory test of heavy mineral analysis. Two synthetic heavy mineral samples were prepared with considerably contrasting compositions intended to resemble natural samples. The contributors were requested to provide (i) metadata describing methods, measurement conditions and experience of the operators and (ii) results tables with mineral species and grain counts. One hundred thirty analyses of the two samples were performed by 67 contributors, encompassing both classical microscopic analyses and data obtained by emerging automated techniques based on electron-beam chemical analysis or Raman spectroscopy. Because relatively low numbers of mineral counts (N) are typical for optical analyses while automated techniques allow for high N, the results vary considerably with respect to the Poisson uncertainty of the counting statistics. Therefore standard methods used in evaluation of round robin tests are not feasible. In our case the ‘true’ compositions of the test samples are not known. Three methods have been applied to determine possible reference values: (i) the initially measured weight percentages, (ii) calculation of grain percentages using estimates of grain volumes and densities, and (iii) the best-match average calculated from the most reliable analyses f

Traditionally, potash mineral deposits have been characterized using downhole geophysical logging in tandem with geochemical analysis of core samples to establish the critical potassium (% K2O) content. These techniques have been employed in a recent exploration study of the Permian evaporite succession of North Yorkshire, United Kingdom, but the characterization of these complex deposits has been led by mineralogical analysis, using quantitative X-ray diffraction (QXRD). The novel QXRD approach provides data on K content with the level of confidence needed for reliable reporting of resources and also identifies and quantifies more precisely the nature of the K-bearing minerals. Errors have also been identified when employing traditional geochemical approaches for this deposit, which would have resulted in underestimated potash grades. QXRD analysis has consistently identified polyhalite (K2Ca2Mg(SO4)4·2(H2O) in the Fordon (Evaporite) Formation and sylvite (KCl) in the Boulby Potash and Sneaton Potash members as the principal K-bearing host minerals in North Yorkshire. However, other K hosts, including kalistrontite (K2Sr(SO4)2) a first recorded occurrence in the UK, and a range of boron-bearing minerals have also been detected. Application of the QXRD-led characterization program across the evaporitic basin has helped to produce a descriptive, empirical model for the deposits, including the polyhalite-bearing Shelf and Basin seams and two, newly discovered sylvite-bearing bittern salt horizons, the Pasture Beck and Gough seams. The characterization program has enabled a polyhalite mineral inventory in excess of 2.5 billion metric tons (Bt) to be identified, suggesting that this region possesses the world’s largest known resource of polyhalite. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution and reproduction in any medium

This project was undertaken in order to document all information concerning the distribution, physical properties and current uses of all the non-limestone ‘hard-rock’ (mainly ophiolite) resources of the UAE. It involved visiting all active and disused aggregate quarries to verify the rock-types used, in what form (i.e. particle size) and for what purpose. With this information a GIS was constructed, in conjunction with the geological maps produced from the previous BGS geological mapping project, in which it was made possible to identify areas of future quarry expansion and new quarry establishment, with various constraints such as environmental concerns. A ‘hard-rock’ usage map was published at 1:100 000 scale, along with this report. Possible future uses of the various rock-types available were considered.

This report describes a suggested new procedure for heavy media separation using non-toxic lithium heteropolytungstate as a replacement for bromoform and other halogenated organic solvents. This work was carried out as part of the Science Facilities’ Maintenance and Development of Capability (MaDCap) project. Lithium heteropolytungstate is commonly known as LST, relating to its composition of lithium, sodium and tungsten. The report firstly describes heavy liquids that were traditionally used for this purpose and then details a new heavy media separation methodology using LST. Results indicate that LST is by far the safest and most efficient heavy liquid suitable for this type of mineral separation. Issues regarding LST stability indicate potential contamination through initial sample preparation methods. A small study indicates that steel swarf from disc milling is responsible for heteropoly blue contamination of the LST and not pyrite as suggested by the manufacturers. It is therefore critical that extreme care should be taken when undertaking any sample preparation prior to heavy liquid separation.

This report presents the results of heavy media separation and the subsequent optical microscopical and mineralogical characterisation of heavy minerals separated from a suite of twenty eight stream sediment samples from Nigeria. The samples were submitted for analysis by Dr Roger Key (BGS) and his team as part of the Nigerian Geochemical Mapping Technical Assistance Project (NGMTAP) which aims to provide baseline geoscientific information for mineral exploration and environmental management through a study of the distribution of important metallic elements. The present investigation follows an initial, pilot mineralogical study carried out on a suite of seven stream sediments samples (Kemp et al., 2009) which in turn was followed by the analysis of a larger batch of sixty stream sediments (Kemp et al., 2010) from the same project. Both studies sought to determine the hosts for elevated levels of zirconium (Zr) and rare earth elements (REEs) in the stream sediments. Zircon was the only Zr-bearing phase identified by XRD in the stream sediments and monazite the only REE-bearing mineral (Kemp et al. 2009, 2010).

This report describes a procedural manual for the newly acquired simultaneous thermogravimetric and differential thermal analysis system and details of initial testing to determine the low level detection and quantification of carbonate species. This work was carried out as part of the Science Facilities’ Maintenance and Development of Capability (MaDCap) project. The report firstly introduces the techniques of thermal analysis and BGS’s capabilities in this area. The report then details a series of experiments designed to determine the low level detection and quantification of carbonate species (calcite, dolomite and siderite). Results indicate that combined TGA-DTA analysis offers significantly lower levels of detection than other mineralogical techniques such as X-ray diffraction analysis. Measured carbonate species concentration levels as low as 200 ppm (dolomite and siderite) and 150 ppm (calcite) in synthetic mixtures are proved. Lower detection limits are possible but proving these is precluded by the difficulty of handling/weighing such small quantities.

This report presents the results of mineralogical characterisation of a further suite of sixty stream sediment samples from Nigeria. The samples were submitted for analysis by Dr Roger Key (BGS) and his team as part of the ‘Technical Assistance Services for the Geochemical Mapping of Nigeria’ project which aims to provide baseline geoscientific information for mineral exploration and environmental management through a study of the distribution of important metallic elements. Particular interest was expressed in determining the hosts for the elevated levels of Zr in the stream sediments. Full sample details, including Zr geochemical data from inductively coupled plasma-mass spectrometry (ICP-MS) are listed in XTable 1X. This study follows a smaller pilot study carried out on a suite of seven stream sediments samples from the same project (Kemp et al., 2009).

This report describes the results of mineralogical and surface area analysis completed on the ‘fine matrix’ (<425 μm material) of a suite of tills from England. The work was carried out as part of the ongoing BGS project, ‘Physical Properties and behaviour of UK rocks and soils’ under the Land Use and Development Science Theme. The first part of the report gives a summary of previous BGS mineralogical studies of till deposits. A summary of analytical methods employed (X-ray diffraction analysis and surface area determinations) is then provided and the results discussed with reference to their likely effect on the engineering performance. Analyses indicate that the till samples are ‘fine matrix’-rich and typically composed of location-dependant varying proportions of quartz, calcite and phyllosilicates/clay minerals together with a range of minor-trace constituents. Given their typically ‘fine-matrix’-dominated nature, the geotechnical behaviour of the till samples examined is likely to be influenced by both the proportion of phyllosilicates/clay minerals present and their composition and can be indicated by the surface area measurements. This being the case, the tills from Thetford (BHs 2 and 5) and Milton Keynes would be expected to show the most problematic engineering behaviour. Although the mineralogy of till deposits are typically thought to be derived from several sources, mineral and clay mineral assemblages suggest that the tills in this study are predominantly derived from underlying lithologies. Tills from various locations in Norfolk other than Thetford appear to be principally derived from the Norwich and Red Crag formations with some input from the Upper Chalk whilst the more carbonate-rich Thetford tills appear to have a greater Upper Chalk input. The mineralogically distinct Lancashire tills suggest Permo-Triassic sources, probably the Mercia Mudstone Group while the Milton Keynes tills indicate that the underlying Jurassic limestones and mudstones pr

This report presents the results of mineralogical characterisation of a small suite of seven pan concentrate samples from Nigeria. The samples were submitted for analysis by Drs Roger Key and John Ridgway (BGS) as part of the ‘Technical Assistance Services for the Geochemical Mapping of Nigeria’ project which aims to provide baseline geoscientific information for mineral exploration and environmental management through a study of the distribution of important metallic elements.

Traditionally, potash mineral deposits have been characterised using downhole geophysical logging in tandem with geochemical analysis of core samples to establish the critical potassium (% K2O) content. These techniques have been employed in a recent exploration study of the Permian evaporite succession of North Yorkshire but the characterisation of these complex deposits has been led by mineralogical analysis. Quantitative X-ray diffraction (QXRD) analysis has consistently identified polyhalite (K2Ca2Mg(SO4)4·2(H2O) in the Fordon (Evaporite) Formation and sylvite (KCl) in the Boulby Potash and Sneaton Potash members as the principal K-bearing host minerals. However, other K hosts, including kalistrontite (K2Sr(SO4)2) a first recorded occurrence in the UK, and a range of boron-bearing minerals have also been detected. Application of the QXRD-led characterisation programme across the evaporitic basin has helped to produce a descriptive, empirical model for the deposits, including the polyhalite-bearing Shelf and Basin seams and two, newly discovered sylvite-bearing bittern salt horizons, the Pasture Beck and Gough seams. The characterisation programme has enabled a polyhalite mineral inventory in excess of 2.5 billion metric tons (Bt) to be identified, suggesting that this region possesses the world's largest known resource of polyhalite., Traditionally, potash mineral deposits have been characterised using downhole geophysical logging in tandem with geochemical analysis of core samples to establish the critical potassium (% K2O) content. These techniques have been employed in a recent exploration study of the Permian evaporite succession of North Yorkshire but the characterisation of these complex deposits has been led by mineralogical analysis. Quantitative X-ray diffraction (QXRD) analysis has consistently identified polyhalite (K2Ca2Mg(SO4)4·2(H2O) in the Fordon (Evaporite) Formation and sylvite (KCl) in the Boulby Potash and Sneaton Potash members as the principal K-bearing host minerals. However, other K hosts, including kalistrontite (K2Sr(SO4)2) a first recorded occurrence in the UK, and a range of boron-bearing minerals have also been detected. Application of the QXRD-led characterisation programme across the evaporitic basin has helped to produce a descriptive, empirical model for the deposits, including the polyhalite-bearing Shelf and Basin seams and two, newly discovered sylvite-bearing bittern salt horizons, the Pasture Beck and Gough seams. The characterisation programme has enabled a polyhalite mineral inventory in excess of 2.5 billion metric tons (Bt) to be identified, suggesting that this region possesses the world's largest known resource of polyhalite.