Sample preparation and analytical methods

Transcription

1 Sample preparation and analytical s Geochemistry, exploration and mining Your laboratory partner

2 Martti Leppä

3 Martti Leppä Sample preparation Rock samples 4 Drying 4 Crushing 4 Pulverising 5 Additional sample preparation s 5 Manual sample preparation schemas 6 Soil and sediment samples 7 Manual sample preparation s 7 Sample analysis Base metal analysis 9 Geochemical analyses (non-mineralised samples) 10 Geochemical analyses (trace levels) 1 Base metal assays 14 Precious metal analysis 17 Geochemical analyses (non-mineralised samples) 19 Precious metal assays 0 Special analyses for gold in metallurgical samples 0 Additional assays Volatiles 1 Determination of carbonate carbon and non-carbonate carbon 1 Chemical phase analysis of base metals Other parameters Petrological analyses Whole rock analysis 3 Rare earth elements 4 Individual determinations 4 Industrial mineral analyses Determination of hydrochloric acid soluble elements 5 Determination of hydrochloric acid soluble elements and insoluble residue of the sample 5 Characterization of waste Leaching tests 5 Acid generation potential evaluation 5 Sample management and storage 6 Abbreviations, accredidation 7 3

4 Sample preparation The objective of a precise sample preparation scheme is to produce a representative and meaningful test sample (regularly about g) from a large bulk sample. The grain size of the prepared sample must be so fine that the element of interest (or host mineral) can be properly liberated from the bulk matrix and distributed in the pulp to produce a homogeneous distribution to ensure sufficient representativity for the following analytical s. This is particularly important for low-concentration ores (e.g. Au and PGE s) where the number of mineral particles producing ore concentration is always low. It is commonly accepted that poor sample preparation is, next to poor sampling, the largest source of bias in an exploration or resource evaluation project. If the representatitivity of the sample is lost during sample preparation, the subsequent assaying cannot correct the damage done. Sample preparation s should therefore be selected as carefully as the actual analytical s. ROCK SAMPLES Drying All samples are always dried no matter what the earlier sample preparation history is (Methods 10/1). Exceptionally wet and large samples (RC-, chip-samples etc.) require longer drying in elevated temperature (Method 14). Preparation Drying in forced air ovens In stainless steel / aluminium trays Crushing Description Drying at 70 C (Rock samples) Max weight 4000 g 10 Drying at 40 C 4000 g 11 Drying at 105 C (RC- and chip samples) Sorting and drying of exceptionally large or wet samples at 100 o C (e.g. RC- and chip samples) 4000 g g 14 Labtium Three options for crushing are available. If the weight of the crushed sample has to be reduced for subsequent steps of sample preparation (subsampling; splitting), the particle size of the crushed sample must be as small as possible. For this purpose fine crushing must be used (s 31 and 33). If the whole sample is to be pulverised a more robust crushing can be used ( ). Preparation Crushing by jaw crusher Description Standard coarse crushing using Mn-steel jaws to nominal 10mm Fine crushing using Mn-steel jaws to nominal 70 % mm Extra fine crushing using Mn-steel jaws to nominal 90 % mm (Boyd crusher) Max weight 4000 g 4000 g g 33 Labtium Sample preparation 4

5 Pulverising Pulverising will always cause unavoidable contamination of wear metals at trace level from the grinding surfaces. This contamination may vary depending on material of the bowl, hardness of the sample material, pulverising time etc. The pulverising must be selected to best serve the requirements of the client. Some examples of bowl materials used at Labtium and expected contamination: carbon steel ( 0. % Fe, no base metals) hardened steel ( 0. % Fe, low Mn, Ni, Cu, Cr, Co) chrome steel (up to 00 ppm Cr, 0. % Fe, traces Mn, Cu, Co) tungsten carbide (W, Co) agate (Si) Preparation Pulverising in ring mill Quartzite cleaner included Grain size of the pulp 90 % 100 μm Description Pulverising the split sample in carbon steel bowl Pulverising the split sample in tungsten carbide bowl (petrological samples) Pulverising a large sample in hardened steel bowl (LM5) (e.g. Drill cores, RC- or chip samples) Max weight 150 g g g 50 Labtium For high-precision whole rock analysis tungsten carbide pulverising must be used. Different minerals behave differently during pulverisation most (brittle) minerals will easily break down to small particles while some (e.g. native gold) will just change their shape if proper sample preparation s are not used. To minimise cross-contamination, cleaning of pulverising bowls between samples (pulverising with barren quartzite) is included in the price in all Labtium pulverising s. The pulverisers and jaw crushers are cleaned with compressed air and brushes between every sample. Additional sample preparation s Preparation Description Max weight Labtium Miscellaneous sample preparation Cutting of drill cores and rock samples Separate splitting/subsampling by riffle splitter (max 5 splittings) to g subsample Separate homogenisation/subsampling by mat-rolling to g subsample Separate splitting/subsampling by rotary splitter Wet sieving to 100 μm, (QC for pulverising) and weighing the +100 μm Compositing/homogenising large pulps in rotary mixer Sawing to two equal halves by diamond saw, returning the other half to original core case, packing the other half to plastic bags or aluminium trays for further processing 4000 g g g g 8 50 kg Sample preparation s should be selected as carefully as the actual analytical s. 5

6 ROCK SAMPLES Manual sample preparation schemas The standard scheme for manual sample preparation consists of direct one-stage fine crushing using a special type of jaw crushers to nominal particle size 70 % mm (Method 31), precision riffle splitting (Method 35), and pulverising the split subsample of g ( 40). This is a suitable if crushed reject is needed for future work. The use of this is meaningful to maximum size of 000 g samples, because if more than 3 4 splittings are required the representativity of the split subsample cannot be assured. For samples containing visible gold and/ or for unusually big or heterogeneous samples, (max. 3,5 kg) we recommend standard crushing (Method ) followed by pulverising the entire test sample (Method 50) in hardened steel bowl using Essa LM5 mills, avoiding any sample splitting which may deteriorate representativity of large samples. The Method 50 is also suitable for pulverising RC (reverse circulation) samples and for percussion drill chip-samples, making crushing and splitting unnecessary. If sample size exceeds 3.5 kg the sample must be pulverised by separate millings and homogenised before subsampling to analytical sample. If crushed reject is required for future work the crushed material can be split to two (e.g. 1 kg) splits (riffle splitting Method 35) the other for storage and the other for pulverising (Method 50). Standard sample preparation of rock samples (max 000 g) Total sample preparation of rock samples (max 3500 g) ROCK SAMPLE DRILL CORE RC-SAMPLE CHIP SAMPLE ROCK SAMPLE DRILL CORE RC-SAMPLE CHIP SAMPLE Storing half of original sample Splitting by sawing Splitting by sawing Storing half of original sample Drying at 70 C / 105 C Labtium code 10/1 Drying at 70 C / 105 C Labtium code 10/1 Jaw crushing (max.0 kg) Fine jaw crusher Nominal 70 % mm Labtium code 31 Jaw crushing Coarse jaw crushing Labtium code Storing coarse reject Subsampling by riffle splitting (max 150 g sample) Labtium code 35 Pulverising the entire sample (max 3.5 kg sample) LM5 mill; hardened steel bowl Nominal 90 % 100 µm Quartzite cleaning after every samples Labtium code 50 Storing pulp Pulverising the split subsample Ring mill; carbon steel bowl Nominal 90 % 100 microns Quartzite cleaning after every sample Labtium code 40 Subsampling from the bowl ( g) or by mat-rolling if requested Labtium code 36 Test sample ( g) Test sample ( g) Additionally riffle splitting (35) can be included after crushing to retain 50 % of the crushed reject. However coarse crushing () has to be replaced by fine crushing (31). Sample preparation 6

7 SOIL AND SEDIMENT SAMPLES Manual sample preparation s For soil samples (e.g. till), we recommend drying at 70 C (Method 10) and sieving to 0.06 mm fraction (Method 4). If mercury or other volatile components are to be determined, lower drying temperatures must be used. High drying temperatures may also cause oxidation of some minerals. Other sieve fractions can be used upon client s request. When requesting sieving, please indicate the fraction to be analysed. If coarse sieve fractions are used for analysis, additional pulverising is regularly required (Method 40). For some purposes, the entire soil sample (weathered bedrock) or a coarse sieved fraction of the sample can also be crushed and/or pulverised. Preparation Description Max weigh Labtium Drying in permeable bags* in forced air ovens Drying at 70 C 4000 g 10 Drying at 40 C 4000 g 11 Sieving to 0.06 mm fraction 1000 g 4 Sieving with nylon sieves Sieving to mm fraction 1000 g 6 Pulverising in ring mill Sieving to other fraction (e.g. 0.5 mm) Pulverising the split sample in carbon steel bowl 1000 g g 40 7

8

9 Sample analysis To obtain the best quality and cost-efficiency in a particular geological project it is important to decide the strategy of analysis by selecting the appropriate analytical s (element suite, digestion/, detection limits, optimum measurement area etc.) to fit the objectives of the project. Selecting a wrong may end up in attaining optimised results in wrong concentration levels and introducing problems in laboratory (contamination, additional sample dilutions) which may deteriorate accuracy and precision. Typically the precision of geochemical s is in the range of 5 10 % and for assays 1 5 %. Base metal analysis Methods The specialists of laboratory will also assist you in selecting the optimised s of analysis for your project. For geochemical exploration for the base metals, we recommend aqua regia digestion of the sample and multi-element analysis by (Method 511P). The package can be upgraded by additional -elements or ICP-MS-analysis to include larger set of elements and lower detection limits (Method 511PM). Although aqua regia is a powerful leaching agent, it still produces a partial dissolution for many elements. The dissolution of silicates and refractory minerals (e.g. baryte, chromite and other spinelles, zircon, cassiterite, tourmaline) varies depending on various factors. Most of the sulphide and oxide minerals (ore forming minerals) are, however, dissolved. The data will also give information on alteration and weathering of rock and till samples. Method 510P is an economic choice when only ore forming base elements are of importance. The is suitable for mineralised samples with moderate grades. There are limitations in the solubility of Ag and Pb at high concentrations, and samples expected to contain more than 5 % of sulphur should be analysed for sulphur using an alternative (e.g. by combustion technique, S-analyser, Method 810L). Total concentrations of trace elements including rare earth elements in geochemical samples can be analysed using multi-acid total digestions and and ICP-MSanalysis (6PM or 7PM). Refractory ore minerals (e.g. chromite, magnetite, ilmenite, columbite, cassiterite etc.), high-grade base metal (e.g. Ni ores) and iron ores and concentrates can also be analysed using alkaline peroxide fusion and multi-element analysis by (70P) or XRF-analysis (176X). Total concentrations are obtained also for major elements. When high quality assays of base metals (e.g. high grade base metal ores and concentrates) are required more representative subsamples and traditional high-precision procedures by (514P). An additional assay is required for samples exceeding the range of the used analytical. 9

10 Base metal analysis Geochemical analyses (non-mineralised samples) Range (ppm) Labtium Aqua Regia Digestion 0.15 g Ag Al As B Ba Be Ca Cd Co Cr Cu Fe K La Li Mg Mn Mo Na Ni P Pb S Sb Sc Sr Th Ti V Y Zn P 31 elements Additional elements by that can be included in the 511P package 0.15 g Bi Dy Hg Rb Te U W Zr P Xx 511P package can be upgraded by ICP-MS analyses to include either individual elements or whole package 511M ICP-MS 0.15 g Ag As Be Bi Cd Ce In Mo Sb Se Sn Te Th U W Yb M Xx or 511PM Sample analysis 10

11 Base metal analysis Geochemical analyses (non-mineralised samples) Range (ppm) Labtium HF HClO 4 HCl HNO 3 Digestion 0. g Ag Al As B Ba Be Ca Cd Co Cr Cu Fe K La Li Mg Mn Mo Na Ni P Pb S Sb Sc Sr Ti V Y Zn Zr P 31 elements Off range samples are analysed with 70P or 176X for base metals and major elements, 810L for S and 705G for Ag. 11

12 Base metal analysis Geochemical analyses (trace levels) Detection limit (ppm) Labtium HF HClO 4 HCl HNO 3 Digestion ICP-MS 0. g Ag Al As B Ba Be Bi Ca Cd Co Cr Cu Fe Hf K La Li Mg Mn Mo Na Nb Ni P Pb Rb S Sb Sc Sn Sr Ta Th Ti U V W Y Zn Zr PM 40 elements Add-on ICP-MS 0. g Ce Dy Er Eu Gd Ho Lu Nd Pr Sm Tb Tm Yb M 13 elements REE Combined ICP-MS 6PM 53 elements REE Sample analysis 1

13 Base metal analysis Geochemical analyses (trace levels) Detection limit (ppm) Labtium HF HClO4 Digestion ICP-MS Add-on ICP-MS 0. g 0. g As Ba Be Bi Cd Co Cr Cu Li Mo Ni Pb Rb Sb Sn Sr Ti Tl V Zn Ce Dy Er Eu Gd Ho La Lu Nd Pr Sc Sm Tb Th Tm U Y Yb PM 0 elements 7M 18 elements Combined ICP-MS 7PM 38 elements 13

14 Base metal analysis Base metal assays Range (ppm) Labtium Aqua Regia Digestion 0.15 g Ag As Cd Co Cr Cu Fe Mn Mo Ni Pb S Sb Zn P 14 elements Range (%) Labtium Sodium Peroxide Fusion 0. g Al As Ba Be Ca Co Cr Cu Fe K La Li Mg Mn Mo Ni P * Pb S Sb Sc Si Sr Ti V Y Zn P 6 elements Aqua Regia Digestion 1.0 g Ag As Cd Co Cu Ni Pb S Zn 1 00 ppm ppm P 8 elements Sample analysis 14

15 Base metal analysis Base metal assays Detection limit (ppm) Labtium Automated pressed powder pellets Determination of carbon is also recommended (Method 811L) XRF 0 g Al As Ba Bi Ca Ce Cl Cr Cu Fe Ga K La Mg Mn Mo Na Nb Ni P Pb Rb S Sb Sc Si Sn Sr Th Ti U V Y Zn Zr X Add-on XRF 0 g Cd F Ta X 15

16 Martti Leppä

17 Sample analysis To obtain the best quality and cost-efficiency in a particular geological project it is important to decide the strategy of analysis by selecting the appropriate analytical s (element suit, digestion/, detection limits, optimum measurement area etc.) to fit the objectives of the project. Selecting a wrong may end up in attaining optimised results in wrong concentration levels and introducing problems in laboratory (contamination, additional sample dilutions) which may deteriorate accuracy and precision. For geochemical the precision is lower than for assay s. Typically the precision of geochemical s is in the range of 5 10 % and for assays 1 5 %. Precious metal analysis Methods In gold and PGE-exploration, both the careful selection of sample preparation and the choice of analytical (including the weight of analytical sample) are critical. Figure 1 shows the effect of the grain size of nugget gold on sample weight for obtaining acceptable precision in gold analysis. We recommend carrying out a pilot study with selected, typical samples of the specified mineralization at an early stage of a large resource evaluation program. The mode of occurrence of gold can be studied using the so-called diagnostic leach and screen fire assay. Replicate analyses of samples can be carried out to study which of the available analytical techniques (and subsample weight) will give acceptable precision (e.g. 5 %) for reliable resource evaluation. Based on this data, a scheme of sample preparation and analysis can be selected for optimum accuracy and precision. A tailored QA/QC-protocol for the project can be planned. The study will also provide information to be used as baseline data for more thorough metallurgical tests. Sample weight 0.1 g 1 g 5 g 0 g 50 g 100 g 500 g 5000 g Diameter of gold sphere (mm) Figure 1 Minimum subsample weight required to contain the expected 0 particles of gold as a function of gold particle size at 4 ppm Au grade (Figure 3 in: Clifton et al. 1969, Sample Size and Meaningful Gold Analysis, U.S.Geol. Surv. Prof. Pap. 65-C, 17 pp.). Different and preconcentration /separation s are available (aqua regia digestion, fire assay, cyanide leach) combined with different s of determination (FAAS; GFAAS; ICP-MS; ; gravimetric), each having its benefits and limitations. Our specialists will assist in the selection of a suitable analytical. In the geochemical exploration for the precious metals (Au, Pd and Pt), we recommend aqua regia leach, followed by pre-concentration by Hg co-precipitation and analysis by GFAAS (Method 51U; 5 g subsample) (Kontas et al. 1990). Sub-ppb detection limits can be attained for Au and Pd giving meaningful anomaly contrasts. The is applicable to non-mineralised samples (till, weathered bedrock, stream sediments, humus, rock). The use of pathfinder elements in geochemical prospecting particularly for gold is known to give more information of element dispersion in secondary environments and assist in the classification of the type of mineralization. This set can be complemented by Methods 511P or 511PM. Another option is a multi-element package using and ICP-MS analysis (515PM). Note that these s are not suitable for mineralised samples. 17

18 Precious metal analysis Ore grade assays of gold and the platinum metals are performed by a high-precision classical Pb-fire assay using either 5 g or 50 g subsamples (704/705), combined with alternative finishes (AAS,, gravimetric). If Au, Pd and Pt are to be analysed we recommend the Method 704P (or 705P). Special precautions need to be taken if samples contain appreciable amounts of graphite, S, As, Te, Se, Ni, Cu. For sample with high concentrations of these metals smaller subsample weight may have to be used deviating from the original request. Gravimetric determination after the fire assay (705G) gives the best precision and accuracy for high-grade ( ppm) gold samples. For concentrates use the s 740G 743G. PAL1000 for simultaneous pulverising and cyanide leach of 0.5 kg subsample As a routine for cyanide soluble gold we recommend Labtium 36A which involves the use of PAL1000-machine. The enables the simultaneous pulverising and cyanide leach of crushed rock samples, percussion samples or soil samples. A kg subsample can be used. The leaching is very effective due to aggressive leaching conditions which promote the liberation and breaking of gold nuggets. Graphite, organic matter (humus) and sulphides interfere in the cyanide leach, lowering the recovery of gold. The concentration of cyanide soluble free gold may also be evaluated using the sodium cyanide leach. The traditional 3 hour tumbling with the LeachWELL accelerator (35A). A large, representative subsample (0.5 kg) can be used. Pulverising of total sample (sample preparation Method 50) must be done before leaching. The cyanidation s are the best possible routine in the case of coarse-grained gold for grade control and resource evaluation samples (e.g. RC-samples, chip samples). The results attained by this partial extraction are comparable to technical CIP- and CIL-extraction techniques and are of benefit in the metallurgical testing of the mineralisation. The is not suitable when the total content of gold is needed. Additional s for gold analysis include screen fire assays for coarse grained gold, diagnostic leaches to evaluate mode of occurrence of gold in different mineralogical phases and analysis of the total gold, which includes cyanide leach and analysis of the tailing (and head, if requested) sample by fire assay. The most suitable analysis for silver is by acid digestion with aqua regia and finish with FAAS (511A/514A) or (510P/514P; see base metals). However, there are potential limitations in the solubility of Ag in high concentrations (Ag 100 ppm). Fire Assay and gravimetric finish (705G) with a more representative sample and better precision can be used for ore grade samples (Ag 50 ppm). In addition metallic silver and copper can be analysed with cyanidation s 35A and 36A as gold. Sample analysis 18

19 Precious metal analysis Geochemical analyses (non-mineralised samples) Range (ppm) Labtium Aqua Regia Leach Hg-coprecipitation GFAAS 5 g Au * Pd * Te U Xx Aqua Regia Digestion ICP-MS 5 g Ag Al As Au B Ba Be Bi Ca Cd Co Cr Cu Fe K La Li Mg Mn Mo Na Ni P Pb Pt S Sb Sc Se Sr Te Ti Th Tl U V W Y Zn Zr ppb ppb PM 39 elements * Analyses of Au and Pd at sub-ppb levels in organic samples (vegetation, humus etc.) based on quotation. Off range samples are analysed with 70P or 176X for base metals, 810L for S and 704P for Au, Pd. 19

20 Precious metal analysis Precious metal assays Range (ppm) Labtium Pb-Fire Assay Gravimetric 5 g 50 g 50 g Au Pd Pt Au Pd Pt Au or Ag P Au or AuPdPt 705P Au or AuPdPt 705G Xx Gravimetric and FAAS/ICPOES 50 g Ag and Au G 705A/P PAL1000-analysis. Pulverising and Cyanide Leach using LeachWELL FAAS 0.5 kg Au Ag Cu A Xx For the analyses of high grade Au- and Ag-ores or check assays Labtium recommends Fire Assay with gravimetric finish. High grade gravimetric Fire Assay of Ag can be combined with FAAS/ICP- OES determination of Au. Analyses of Ag see also Base Metals (s 510/514P). Special analyses for gold in metallurgical samples Concentrates (e.g. flotation concentrates) High grade concentrates (e.g. gravity concentrates) Gold in carbon Commercial assays, bullion and umpire assays Screen Fire Assay for coarse gold Free and refractory gold Pb-Fire Assay (sample weight varies 5 g) with gravimetric finish. Includes sample preparation and representative subsampling using precision rotary splitter. Concentration range ppm Au. Assay of Au, Pd and Pt by Pb-Fire Assay (sample weight varies 5 g) with gravimetric finish. Includes sample preparation and representative subsampling using precision rotary splitter. Concentration range % Au. Ashing, digestion with aqua regia, analysis by ICPOES/FAAS Additional elements can be included. Fire assay analysis by gravimetry (ASTM E1568) Sieving of a 0.5 kg subsample with a 15 µm (10 mesh) sieve. Weighing each fraction. Fire assay (Method 705A/P) of the entire +15 µm fraction. Duplicate Fire assay (Method 705A/P) of -15 µm fraction. Calculation of weighted concentrations of gold (total and fractions). Cyanide leach of a 0.5 kg subsample (Method 36A). Washing, neutralising and homogenising the tailing. Duplicate Fire Assay (Method 705A) of the tailing. 740G 740P 741G 518P 740G G 709P 39A Sample analysis 0

21 Additional assays When the ore forming mineral is exceptional or when total concentrations for geochemical or petrological studies (trace levels of elements) are required, please contact the laboratory for assistance in selecting the best possible digestion/ for your purpose. Methods In addition to classical geochemical s, a selection of selective leaches (using water extraction, ammonium acetate, pyrophosphate etc.) combined with ICP-MS-analysis is also available for geochemical exploration of buried ore deposits. The set of elements is comparable to 511MP or 515MP. Elements in specific mineral phases of the sample can also be determined, such as Ni in the sulphide phase or elements in the carbonate phase of the sample. Special s are available e.g. for the determination of mercury, total sulphur and carbon (Combustion; Method 810L) or sulphur and carbon mineral phases. Volatiles Combustion technique Detection limit Labtium Hg-analyzer 0.1 g Hg ppm 8L Ignition Gravimetric 1 g LOI Loss on ignition at 1000 C % 813G Combustion technique S/C-analyzer 0. g S C % % 810L 811L Determination of carbonate carbon and non-carbonate carbon Combustion technique Detection limit Labtium C-analyzer g C-tot. 100 ppm 811L Treatment with HCl C-analyzer g C-carb. C-noncarb. 100 ppm 100 ppm 816L 1

22 Chemical phase analysis of base metals Range (ppm) Labtium Ni, Cu and Co in sulphide minerals Ammonium Citrate H O Leach 0.15 g Cu Ni Co Fe (S) ( ) 40P Bromine Methanol Leach FAAS 0.15 g Cu Ni Co Fe A Ni and Cu in oxide minerals Sulphuric acid Sodium sulphite Leach 0. g Cu Ni P Individual and sequential leaches can be tailored for the chemical phase analysis of base metals. Other parameters Determination Elements Range (ppm) Labtium Specific Gravity Saturation Magnetization Gas pycnometer SG g/cm 3 8G Satmagan Fe3O4 % 891G Additional assays

23 Petrological analyses Whole rock analyses are carried out using high precision s applying state-of-the-art instrumentation (XRF,, ICP-MS). Major, minor and many trace elements are determined by XRF. Determinations are made on pressed powder pellets (Method 175X). The XRF analysis can be supplemented by determination of the rare earth elements and other trace elements by ICP-MS and/or after the total digestion of the sample (Method 7PM or 8M). Carbon (Method 811L) and loss on ignition (Method 813G) are recommended for complete whole rock analysis. Individual determinations, which are often required in whole rock analysis, such as iron (II), fluoride, HO+ and HO-, are also available. The XRF is applicable to rocks and soil samples, such as sand, gravel, till and sediments. Technical products and ash of similar composition can also be analysed. The prerequisite for applicability of the XRF is that the chemical composition of the sample remains unchanged during the fine grinding ( 10 μm) as the pressed powder pellet is prepared. Samples containing 0 % S cannot be analysed by this. Whole rock analysis Detection limit (ppm) Labtium Pressed powder pellets Determination of carbon is also recommended (Method 811L) XRF 7.0 g Al As Ba Bi Ca Ce Cl Cr Cu Fe Ga K La Mg Mn Mo Na Nb Ni P Pb Rb S Sb Sc Si Sn Sr Th Ti U V Y Zn Zr X Add-on XRF 7.0 g Cd F Ta X 3

24 Rare earth elements Detection limit (ppm) Labtium HF HClO 4 Digestion Lithium metaborate Sodium perborate Fusion ICP-MS 0. g Ce Dy Er Eu Gd Ho La Lu Nd Pr Sc Sm Tb Th Tm U Y Yb Additional elements: Co Hf Nb Rb Ta V Zr M 8M For other elements contact laboratory. Individual determinations Detection limit (%) Labtium Ignition Gravimetric 1 g LOI Loss on ignition 1000 C 813G Combustion technique HO analyzer 0.5 g Moisture Cryst. water 815L Acid Digestion HF H SO 4 Titrimetric 0.5 g Fe T NaOH Fusion Potentiometric 0.1 g F 75I Petrological analyses 4

25 Industrial mineral analyses Determination of hydrochloric acid soluble elements (recommended ) Detection limit (ppm) Labtium Hydrochloric acid Digestion 0.1 g Al Ca Mg Fe Mn P Determination of hydrochloric acid soluble elements and insoluble residue of the sample Detection limit (ppm) Labtium Hydrochloric acid Digestion 1.0 g Al Ca Mg Fe Mn P Gravimetric 1.0 g Insoluble residue 0.3 % 406G Characterization of waste Leaching tests Compliance test for leaching of granular waste materials and sludges Leaching behaviour test. Up-flow percolation test EN EN EN EN CEN/TS ph and EC EN 1506 Element analyses by and ICP-MS EN 1506 Hg EN 1785 Anions EN 1506 EN TDS EN 1516 DOC EN Acid generation potential evaluation Acid Base Accounting (ABA) Static test for sulfidic waste Neutralisation Potential, NP Acid Potential, AP Neutralisation Potential Ratio, NPR Net Neutralisation Potential, NNP Net Acid Generation (NAG) Single NAG Sequential NAG SFS-EN 15875:en AMIRA ARD Test Handbook Project P387A ph EN 1506 Total Sulfur (pyrolysis) ISO Total Carbon (pyrolysis) CEN Carbonate Carbon EN (Mod.) 5

26 Sample management and storage Systematic and well-organised sample archiving is not always thought to be included in the quality management of an exploration project. Good archiving helps the future retrieval of samples for e.g. feasibility testing and replicate or umpire analysis. Methods During future audits of the project, well organised archiving is one of the fundamental issues. At Labtium special attention is paid on labelling and storing of all materials. The laboratory samples are stored in paper/plastic bags. Pulps and/or rejects are stored in sealed plastic bags in pallets. All the packing materials except for pallets are included in the prices. Sample batch reception (901) includes checking the sample numbering, sorting etc. and packing materials. The cost for long term storage of drill cores, rejects and pulps (906) and laboratory samples (907) can be negotiated. For all samples a laboratory waste management fee is invoiced to cover the expense of hazardous waste disposal (903). If the client does not want the rejects and pulps to be returned a waste management levy is invoiced (90). If sample batches are arriving in the laboratory highly disorganised the laboratory is forced to invoice also the reorganising of the field samples (904). Also if the sample bags or containers are damaged, the replacement of the samples to new containers has to be invoiced (905). Reception fee for a batch of samples 901 Waste disposal fee for reject sample materials 90 Disposal fee of laboratory waste 903 Organising received disorganised samples 904 Removing samples from damaged/unsuitable containers to new containers/bags 905 Storage of pulps/rejects after 1 months from reporting 906 Storage of laboratory samples after 1 months from reporting 907 Disposal of cyanide waste 915 Sample management and storage 6

27 ABBREVIATIONS Analytical technique GFAAS FAAS Description Atomic Absorption Spectrometry, electrothermal atomisation Atomic Absorption Spectrometry, flame atomisation Labtium code U A AFS Atomic Fluorescence Spectrometry F XRF ICP-MS S/C-ANALYZER Wavelength Dispersive X-ray Fluorescence Spectrometry Inductively Coupled Plasma Optical Emission Spectrometry Inductively Coupled Plasma Mass Spectrometry Combustion, IR-detection, Sulphur or Carbon analyser Weighing Gravimetric G X P M L Units ng = 10-9 g μg = 10-6 g mg = 10-3 g ppb = ng/g = μg/kg = mg/t ppm = μg/g = mg/kg = g/t ACCREDITATION Labtium Ltd. is an accreditaded testing laboratory. The accreditation according to ISO/IEC 1705 was received originally in 1994 from the Finnish Accreditation Service, FINAS. The accreditation code of Labtium is FINAS T05. The up-to-date scope of the accreditation can be found in The FINAS accredited bodies may state in their reports and certificates that they are accredited by FINAS, which is a signatory of the EA (European cooperation for Accreditation), ILAC (International Laboratory Accreditation Cooperation or IAF (International Accreditation Forum Inc.; recognition agreement. Thus a global acceptance and recognition of the accreditation and quality system of Labtium Ltd. is achieved. Labtium Ltd. is continuously participating in independent, international proficiency tests in the mineral sector run by e.g. Geostats Pty Ltd., Australia and the GeoPT sponsored by the International Association of Geoanalysts (IAG). In addition Labtium participates in a proficiency test for Canadian accredited mineral testing laboratories (CANMET PTP-MAL). These tests are used to evaluate the performance and validity of our s in comparison to other international mineral testing laboratories. The reports are available to clients on request. Hanna Kahelin Quality Manager 7

28 Labtium Oy/Ab/Ltd. Business ID firstname.lastname@labtium.fi Contacts Heikki Niskavaara Business director Espoo Kaarina Fagerholm Laboratory manager P.O. Box 57 (Tekniikantie ) FI-0151 Espoo Kuopio Susanna Arvilommi Laboratory manager P.O. Box 1500 (Neulaniementie 5) FI-7011 Kuopio Lea Hämäläinen Business director Jyväskylä Janne Nalkki Business director Koivurannantie 1 FI Jyväskylä Outokumpu Pekka Parvinen Senior specialist P.O. Box 45 (Tutkijankatu 1) FI Outokumpu Sodankylä Toni Malila Chemist P.O. Box 97 (Poikajuntintie 34) FI Sodankylä Hahmo Design 10/015 Cover photo: Martti Leppä