Methodologies Open or Close
X-RAY FLUORESCENCE SPECTROSCOPY (XRF)
XRF is a non-destructive analytical technique used to determine a full range of light to heavy elements by pressed pellet or fused disc. Pressed pellet is a low cost test, suitable for large numbers of samples (usually ppm levels) where the matrix of the material is generally consistent. Good examples of this application are copper and nickel determination in Merensky, UG2 and Platreef mineralization of the Bushveld Igneous Complex in South Africa, or analysis of uranium hosted by siliceous rocks. Fused disc analysis involves fusion of the material into a borate glass disc for analysis of the major elements, covering ranges of 0.01 to 100% for many of these elements.
X-RAY DIFFRACTION (XRD)
Polycrystalline phases of a solid material are determined by X-Ray Powder Diffraction.
Angles of diffraction originating from a sample which is irradiated by a beam of monochromatic X-Rays, are measured and recorded by a diffractometer. Based on the originating pattern, a crystal can be identified and characterized. Our Laboratory hosts a database in excess of 150 000 crystalline phases. The minerals and crystalline inorganic phases that comprise a specimen can be identified by means of a computerised search/match system.
In addition, our quantification software, which is based on the Rietveld method of mineral and inorganic crystal quantification, provides standardless quantitative phase analysis.
INDUCTIVELY COUPLED PLASMA OPTICAL EMISSION SPECTROSCOPY (ICP-OES)
ICP-OES is one of the most versatile methods of inorganic chemistry covering large ranges from ppm to percentage levels of most elements. A variety of digestions are offered with this technique such as aqua regia (oxide, sulphide and carbonate material, but not silicates), four acid (provides a total dissolution of most elements except for a few such as Cr, V and Ti) and peroxide fusion (suitable if the non-soluble elements of the four acid digestion are required). Other dissolution techniques such as acid soluble copper (oxide copper) are also available.
INDUCTIVELY COUPLED PLASMA MASS SPECTROSCOPY (ICP-MS)
This technique is usually done in conjunction with ICP-OES and allows analysis down to lower ppm levels and sometimes ppb levels.
LECO, UV-VIS, CALORIFIC VALUE AND OTHER INSTRUMENTAL TECHNIQUES
These techniques are for analyses of carbon and sulphur, or chloride and cyanide.
WET CHEMICAL ANALYTICAL TECHNIQUES SUCH AS TITRIMETRY AND GRAVIMETRY
When dealing with percentage levels such as mineral concentrates, Wet Chemistry is often the most accurate technique to offer. Examples are chromium, iron and manganese by titration, and silica gravimetric analysis.
Sample Preparation Open or Close
SAMPLE PREPARATIONAnalytical Sample Preparation is one of the most important steps in the analytical testing process. The goal is to achieve a homogenous sample or a sub-sample that is representative of the submitted material. If this is not achieved, then the analytical result can be biased or even meaningless! Set Point Laboratories uses hi-tech crushing and milling equipment, with the sample preparation procedures accredited as separate entities on their own – apart from sample analysis itself.• Samples are checked and sorted according to client’s submission sheet• Every batch of samples has an information sheet• Samples are inspected for any trace of moisture, if they require drying we place them in the drying oven at temperatures until they are dry• Each sample is weighed on the top pan balance and its weight is recorded in the LIMS system• Primary: We crush the rocks, rock chips or lumps using a jaw crusher and place the crushed material into a clean and labelled plastic bag• Secondary: We then crush the resulting chips to a fineness of 90% less than 2.0mm• If the sample requires splitting, we split it using a Jones riffle splitter, the split is placed into a new sample bag and the remaining sample (coarse reject) will be returned to the client.• The sample is milled to achieve a fineness of 90% less than 106µm or 80% passing 75µm• After milling, the contents of the bowl are emptied onto a brown paper sheet and transferred into the sample bag.• Once a batch of samples is completed, they are repacked for analysis.
Laboratory Quality Control• One out of every 10 samples passing through the secondary crusher is screened at 2.0mm to check that 90% of the material passes• One out of 10 samples of every batch is screened at 75µm or 106µm, whichever is applicable , to check that percentage of the material passes• Percentage loss for samples screened should be <2%• Clean bowls , discs and lids with cleaning running water and compressed air between each
Water Testing and Analysis Open or Close
WATER TESTINGA market leader in the water testing field, Set Point Water Laboratory has proven to be every customer’s choice when it comes to analysis of ground, surface, drinking, waste and processed water just to mention a few.We serve a massive customer base from private individuals who might be concerned with the quality of borehole and municipal water supply to water industry consultants, water treatment companies, Mines, Wet industries, Local, Provincial and National Government as well as other laboratories that require our analytical laboratory services.Various internationally recognised techniques such as Photometric, Electrometric, Colometric, ICP-OES and ICP-MS and Enzyme Substrate are used to obtain the best possible results in Chemical and Microbiological analysis of water. Tests carried out include physical and aesthetic properties of water, nutrient analysis, macro and micro chemical determinants as well as general microbiological analysis.Services offered include the chemical analysis of:• Drinking water ,to test compliance with National Drinking Water Standards• Environmental ,mine and surface water to test compliance to National Water Act• Waste water, to test compliance to National Water Act as well as individual permit and licence agreement• Industrial effluent, to test compliance to Municipal by-lawsCustomers can expect the following:• Accurate results• Quick turnaround time• Reasonable prices• User friendly reportsFor a quick quotation on water testing and analytical laboratory solutions, contact our highly qualified and friendly analysts who will not only assist you in selecting the appropriate tests but will advise you on water related problems and interpretation of results.CHOOSE SET POINT
Fire Assay Open or Close
FIRE ASSAYDetermination of Gold and Platinum Group Metals (PGMs) by lead collection, ICP-OES finish.
PROCEDURE• Gold, platinum and palladium are collected by lead collection Fire Assay using silver as a co-collector to facilitate easier handling of prills as well as to minimise losses during the cupellation process.• A catch weight of sample is mixed with 200g of fire assay flux and spiked with silver.• The mixture is loaded into a furnace and left for at least 55 minutes.• The resulting melt is poured into moulds and left to solidify.• During cooling of the melt, a lead button settles to the bottom of the mould and is separated from the slag.• The button is then cupelled for 60 minutes to remove the lead, leaving behind a prill, containing the silver, gold and PGMs of interest.• The prill is digested using Hydrochloric and Nitric acid and made up to a 5ml volume.• The resulting solutions are used for gold testing, platinum testing and palladium testing by the technique of ICP-OES (Inductively Coupled Plasma – Optical Emission Spectrometry).
Determination of Rhodium by lead collection is done using the same procedure as the silver prill collection, but substituting palladium in the place of the silver.
QUALITY CONTROLThe samples are handled in batches of up to 50, being the size of the furnace tray.Each batch of 50 samples shall contain one blank sample, two QC samples and 2 duplicates. These duplicates are repeats of randomly chosen samples from the batch. Batches of less than 50 samples shall contain at least one duplicate, one QC sample and a blank.Additional repeats may also be done upon evaluation of the results. These samples to be repeated shall be selected by looking for obvious outliers or chosen randomly by experienced chemists.The value obtained for the QC sample/s shall be within specified control limits.
Determination of Platinum, Palladium, Rhodium, Iridium and Ruthenium by NiS collection, ICP-MS finish
PROCEDURE• PGMs in samples are collected in a single fusion step, using the nickel sulphide (NiS) fusion technique.• The NiS buttons are subjected to leaching, precipitation and filtration processes in order to separate the PGMs.• The PGMs are dissolved using aqua regia. The resulting solutions are analysed by ICP-MS (Inductively Coupled Plasma – Mass Spectrometry) to determine the concentrations of Pt, Pd, Rh, Ir and Ru contained in a sample.
QUALITY CONTROLThe samples are handled in batches up to 35. Each batch of 35 samples (or less) shall contain one blank sample, one QC sample and 1 duplicate. These duplicates are repeats of randomly chosen samples from the batch.Additional repeats may also be done upon evaluation of the results. These samples to be repeated shall be selected by looking for obvious outliers or chosen randomly by experienced chemists.The value obtained for the QC sample/s shall be within specified control limits.
ICP (INDUCTIVELY COUPLED PLASMA OPTICAL EMISSION SPECTROSCOPY)ICP analysis is one of the most versatile methods of inorganic chemistry covering large ranges from ppm to percentage levels of most elements.Set Point Laboratories uses this technique to determine the concentration of metals and metalloids at trace, minor and major concentrations. A variety of digestions are offered with this technique such as Aqua Regia (partial dissolution ), four acid (total dissolution of most elements except for few such as Cr, V, Ti) and Peroxide fusion ( which is suitable if the non-soluble elements of the four acid digestion are required).ICP is used to analyse Fire Assay samples, i.e. Lead collection which is used to accurately determine Au, Pt, Pd (and Rh if required) and Nickel Sulphide collections which determines all PGE elements (6E) and offers up to 42 multi elements scan package.ICP-OES is usually done in conjunction with ICP-MS( Inductively Coupled Plasma Mass Spectroscopy) which is used to accurately determine lower detection limits, ppb levels
BASE METALS AND MULTI ELEMENTSDepending on the testing requirements, XRF or ICP-OES / ICP-MS can be employed to offer a full range of testing services for base and multi elements.
URANIUM AND RARE EARTHS
Set Point Laboratories offers a range of earth analysis by XRF,ICP AND ICP-MS. We are accredited for U-analysis by XRF pressed pellet and are a certified member of NNR.
Coal Analysis Open or Close
Coal AnalysisSet Point offers various analytical services for coal such as sample preparation of test samples, determination of floats and sinks, apparent relative density of coke, sieve analysis, proximate analysis of coal, total sulphur, forms of sulphur, gross caloric value, ash constituents, crucible swelling Index and many more.o Float and Sink- this process involves the separation of a coal sample into more relative density fractions. The density fractions are de-fixed by lower value at which the material sinks and upper value at which the material floats.
o Sample Preparation - this is to prepare a test sample that will pass a sieve of nominal size of openings 212um.o Sampling (stockpile sampling)o Relative densityARD (apparent relative density)- The volume of a large amount of coke is determined by displacement in water-dividing the mass of dried coke by the mass of an equal volume of water.Insitu RD (true relative density) -the mass of water is displaced by a known mass of dry coke/coal, ground to pass a 212um,is determined by using pyknometer.o PSD(particle size distribution)/ Size analysis - Involves the separation of a sample of coal into size fractions having defined limitso Proximate Analysiso Ash – The test portion is heated in air at a specified rate up to a temperature of 815°C ±10°C and maintained at this temperature for 60min.o Volatile – A portion of the sample is heated out of contact with air at 900°C for 7min. The percentage of volatile matter is then calculated from the loss in mass of the test portion after deducting the loss in mass of moisture.o Moisture – A known mass of cola is heated at temp between 105°C and 110°C and maintained at this temp until it is constant in mass. The moisture content is calculated from the loss in mass of the coalo Fixed Carbon-by calculationo Total Sulphur - This is determined by the high temperature combustion / IR absorption method of analysiso CV - A weighed portion of the analysis sample is burned in high pressure oxygen bomb calorimeter under specific conditions.o Trace Elementso Ash constituents(XRF)o Phos(XRF)o Ultimate analysis and many more