LABORATORY LABORATORY SERVICES. 1. Sample preparation

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1 Applied Geoscience Solutions LABORATORY LABORATORY SERVICES Established in 1897, the Council for Geoscience Laboratory continues to develop and grow. Our facility offers world-class analytical and consultative services in primary solid sample preparation, mineralogy, petrology, geochemistry, ceramics and coal analyses as well as for specialised research in applied mineralogy, coal, the environment, petrology and geochemistry. We constantly strive towards professionalism and good customer relations. We encourage skills development in alignment with the capacity, performance and expertise of our laboratory services. The laboratory offers analytical and research services that meet the exact requirements of our clients. Our services are of superior quality and comply with national and international standards. Analyses and asessments are done on rocks, soils, minerals, water and industrial and waste materials to determine various qualitative and quantitative aspects of mineralogy, petrology, physical chemistry and the ceramic sciences. The availability of a range of instrumentation enables our analysts to employ multidisciplinary approaches in solving problems and assisting our clients in the evaluation of their data. The services offered by our laboratory include the following: A. LABORATORY TECHNIQUES Our facility offers analytical and research techniques that are aligned with international methods and designed to meet our clients needs. Our products are of superior quality and comply with national and international standards. The availability of a range of instruments and techniques enables our scientists and technical staff to employ multidisciplinary approaches to solve problems and to assist clients in the evaluation of their data. The facility has the following dedicated competencies: 1. Sample preparation A fully equipped sample preparation facility is available that plays a vital role in providing our analysts with compositionally representative 1

2 2. Petrography Rocks, soils, ores and many other materials consist of minerals. The study of mineralogy is therefore crucial to the understanding of the composition, occurrence, physical properties and classification of these materials. Additionally, petrology explores the origin, history and structure of igneous, metamorphic and sedimentary rocks, as well as soils. Petrographic techniques offered by the laboratory include: Fig.1 Jaw crusher. subsamples of rocks, soils and ores, sediments and any other solid sample type of mainly geological origin submitted by our clients. A series of specialised instruments, including jaw crushers, rotary splitters and mills are available to fracture, reduce and pulverise samples to a homogeneous powder with a particle size of up to less than 75 microns. Basic and detailed descriptions of rocks and modal and strain analyses. Analyses for the alkali-aggregate reaction potential of rocks used in construction. Petrographic sample preparation services are available and include the cutting of rock samples to make standard and large-format polished thin sections, the production of double-polished wafers and the polishing of rock specimens and stubs. Fig.2 Rotary splitters. Fig.3 Polishing machine. 2

3 A mineral separation facility is available where specific mineral concentrates can be extracted from geological samples. Heavy mineral separates are routinely prepared for various geological investigations, most commonly zircon for the age determination of igneous rocks suites. Fig.5 X-ray diffractometer. Fig.4 Petrographic quality assessment microscope. 3. Mineralogy (XRD, SEM and ceramics) Fig.6 Scanning electron microscope with EDS. X-ray Diffraction (XRD) is a basic and widely used investigative technique in mineralogy. The qualitative and quantitative mineral composition of a sample can be estimated, polytypes, in particular, can be identified and the crystallinity of mineral species can be assessed. XRD is an extremely powerful tool used for the examination of clay materials. The Scanning Electron Microscope (SEM) with a microanalysis system (Energy Dispersive Spectroscope EDS) attached to it is utilised for imaging and the X-ray microanalysis of rocks, minerals and industrial materials. Scanning Electron Microscopy is widely utilised in applied mineralogy investigations and increasingly more in environmental studies where the 3

4 characterisation of microscopic particulate matter is required. 4. Chemistry Chemical analyses of research quality are routinely performed on soil, mineral, water, industrial and waste materials using state-ofthe-art instrumentation. A consultation service is offered to assist in data interpretation, sampling or analytical techniques as well as in the development of new analytical methods. Fig.7 ED-XRF. In conjunction with other analytical techniques, SEM is a strong tool for solving various industrial problems associated with soil/water contamination, process control, product failure/ corrosion and product development. It provides the researcher with topographic imaging of the material surface with qualitative and quantitative compositional information of the matrix to assist in scientific problem solutions and enhances the quality of the scientific research product. Geological samples are routinely decomposed using fusion or acid digestion and analysed for their major, trace or rare earth element composition using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) or Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Matrices such as coal or peat are analysed using ICP-MS. Solid samples are analysed for their mercury, carbon or sulfur contents using direct analysis instruments. The ceramics section of the laboratory evaluates the physical properties of new raw material prospects and those of existing quarries for use in the brick and tile industries. The ceramics section routinely characterises raw materials in terms of their mineral and chemical composition, assists industry with research and the development of product mixes and with problem solving in respect of raw materials, firing and other aspects of manufacturing. The section is also in the position to do exploration work and to characterise new raw material deposits. Fig.8 An ICP-MS spectrometer. Water samples are analysed in order to determine their major and trace metals as well as metalloids content using ICP-MS. Anions are determined using a discreet analyser. 4

5 A wide range of sample types such as rocks, soils, ceramics, building materials, mineral wastes, sediments and ores are analysed in respect of major and trace elements. Our scientists also offer a consultation service to assist in data interpretation, sampling, research and the development of customised analytical services. Fig.9 A discreet analyser. 5. XRF X-Ray Fluorescence (XRF) spectrometry measures the emission of characteristic secondary (or fluorescent) X-rays from a material that has been excited by bombardment with high-energy X-rays. One of the state-of-the-art XRF spectrometers in our facility is equipped with simultaneous technology for the quick analysis of large batches of samples (e.g. for geochemical exploration, mapping or large sampling projects). 6. Coal The facility has the capability of conducting coal, biomass, char, mine tailings, oil and shale quality assessment analysis with various well-known analytical methods using modern analytical instruments. We use standard SABS and ASTM and ISO methods for secondary sample preaparation and for analysis. The section also participates in the following international and national intralaboratory proficiency testing schemes: Coal Concept and Coal Spec. Some of our scientific staff are accredited in different areas within the coal petrography discipline. The following analytical assessment services are offered: i. Proximate analysis Ash Moisture Volatile matter Fixed carbon by difference Fig.10 An energy dispersive-wavelength dispersive XRF spectrometer. ii. Ultimate analysis Carbon Hydrogen 5

6 Nitrogen Total sulphur iii. HPVA (100 bar) capacity gas absorption isotherms Coalbed methane gas adsorption measurements CO 2 gas storage measurements for CCS (carbon capture and storage) Shale gas adsorption measurements Surface area analysis Fig.13 Coal petrographic microscope. Fig.11 HPVA gas adsorption isotherm. iv. Coal petrography (accredited by the International Committee for Coal and Organic Petrology) Maceral analysis Vitrinite reflectance analysis Dispersed organic matter by vitrinite reflectance measurements Microlithotype analysis Carbon particle type analysis v. Free swelling index vi. Calorific value determinations. Fig.12 CHNS furnace. The coal laboratory section participates in international and national proficiency testing programmes to ensure that it adheres to good quality standards which leads to good quality 6

7 results. The coal petrography process is ICCP accredited for single coal and coal blend ICCP accreditation programmes. The coal laboratory section has competent staff who are well trained in all the coal quality assessment analytical methods of the section. frequency domain) ix. Dielectric parameter analysis x. Seismic velocity (p-wave and s-wave). 7. Petrophysics The facility focusses on the measurement of physical rock properties directly related to geophysical methods. Our facility boasts a well-equipped section for the measurement of palaeomagnetic and physical properties. Fig.15 Ultrasonic pulse velocity instrument. Fig.14 Spinner magnetometer. The section is capable of performing measurements of the following properties: i. Magnetic susceptibility (mass and volume) ii. Anisotropy of magnetic susceptibility (AMS) iii. Normal remanent magnetisation (NRM) [direction and intensity] iv. Thermomagnetic analysis v. Magnetic remanence and Königsberger ratio vi. Bulk density (wet and dry) vii. Electrical resistivity (time domain and frequency domain) viii. Induced polarisation (time domain and Fig.16 Time-domain resistivity and sample core induced polarisation (IP) tester. 7

8 A database containing physical property data from a wide range of South African lithologies is available for queries. 8. Environmental analyses The facility undertakes laboratory-based investigations of natural and anthropogenic contamination. Test methods and services currently available are: i. Acid-base accounting (ABA) ii. Paste ph and electrical conductivity (EC) iii. Sequential extraction iv. Inorganic toxicity characteristic leaching procedure (inorganic TCLP) v. Alkalinity test vi. Acidity test vii. Batch leach viii. Multistage batch leach ix. Column leach x. Humidity cell leach testing. B. CONTACT US AT: Tel. 1: Tel. 2: : info@geoscience.org.za 2: laboratory@geoscience.org.za website: Our terms and conditions are available on our website or on request Fig.17 Autotitrator burette stand. Our pricelist is available on request. 8