GEOLOGYGEOTECHMININGPROCESSINGVALUATION/RISKTECHNOLOGIESENVIRONMENTTRAINING Sampling Case Studies Presented by Mark Noppe At IQPC Mine Site Sampling, Brisbane May 2013

Xstract - Excellence from the Outset XstractGroup.com Content Importance of sampling Sampling errors Channel sampling Riffle sampling Coal sampling Pulp sampling QA/QC data Bulk density Databases 2

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Xstract - Excellence from the Outset XstractGroup.com Importance of sampling 4

Xstract - Excellence from the Outset XstractGroup.com Where sampling errors occur 5

Xstract - Excellence from the Outset XstractGroup.com Sampling error 6 Going from the bottom up, all the errors are accumulated in a Sampling Error

Xstract - Excellence from the Outset XstractGroup.com Analytical error 7 The Analytical Error arises from the technique or instrument used to analyse the sample Do you think this error is large or small?

Xstract - Excellence from the Outset XstractGroup.com Sample collection error 8 The Sample Collection Error is the sum of all the errors below it

Xstract - Excellence from the Outset XstractGroup.com Localisation error 9 The Localisation Error is the error that arises from poorly locating the sampling points

Xstract - Excellence from the Outset XstractGroup.com Materialisation error 10 The Materialisation Error is the sum of the Delimitation and Extraction Error (DE and EE) and the Grouping and Segregation Error (GSE) DE and EE both relate to obtaining the sample

Xstract - Excellence from the Outset XstractGroup.com Channel sampling: Zambia copper, Brazil gold 11 Samplers selectively sampling ore zone

Xstract - Excellence from the Outset XstractGroup.com Mali gold – overwhelmed riffle sampling 12 Riffle splitter versus automatic RC chip sampling Good example of use Incorrect use of splitter

Xstract - Excellence from the Outset XstractGroup.com Riffles and cones 13 Three-tiered riffle splitter

Xstract - Excellence from the Outset XstractGroup.com Cone sampler 14 Cone splitter

Xstract - Excellence from the Outset XstractGroup.com Coal examples 15 Loss of fines during drilling and/or sampling Poor recovery, effects typically bright (good quality coal bands) Coal and/or coking yield assessment

Xstract - Excellence from the Outset XstractGroup.com Coal examples 16 Indonesia – parting not sampled, coal qualities overstated Coal seams

Xstract - Excellence from the Outset XstractGroup.com Coal examples 17 Shift sampling – shift sample tampering

Xstract - Excellence from the Outset XstractGroup.com Segregation error – pulp sampling 18 Gold mine – gold pulp sampling bias

Xstract - Excellence from the Outset XstractGroup.com QA/QC data analysis 19 Alumina XRF – trends in data overlooked

Xstract - Excellence from the Outset XstractGroup.com QA/QC data analysis 20 DRC – no correlation between duplicates

Xstract - Excellence from the Outset XstractGroup.com Bulk density sampling 21 Grab samples for grade control – used in model too, not “air dried”, no moisture adjustment, poor use of grab sample, no correction for “vugghy” samples Moisture content?

Xstract - Excellence from the Outset XstractGroup.com Bulk density sampling 22 Belt sampling – seasonal moisture issues

Xstract - Excellence from the Outset XstractGroup.com Database errors 23 % or ppm, particularly for cobalt from mixed database sources

Xstract - Excellence from the Outset XstractGroup.com Thank you for your attention For any follow up questions or enquires please contact: Mark Noppe Managing Director & Principal Consultant Xstract Mining Consultants Pty Ltd Offices Brisbane, AustraliaPerth, Australia Phone: Phone: Adelaide, AustraliaNewcastle, Australia Phone: Phone: Ulaanbaatar, MongoliaLondon, United Kingdom Phone: Phone: Xstract - Excellence from the Outset XstractGroup.com