Advanced indicator mineral research concept for the CRM exploration in glaciated terrain – INDIKA project
Marja Lehtonen, Pertti Sarala, Anne Taivalkoski, Sari Lukkari, Irmeli Huovinen, Jouko Karinen, Hanna Koskinen, Kari Strand, Rauno Toppila & INDIKA Project Working Group Critical Raw Materials
EU Mineral Strategy: Increase of self-sufficiency, production and reserves of critical, high technology metals and minerals
http://ec.europa.eu/growth/sectors/ra w-materials/specific-interest/critical_en
• Link to industry • Modern technology • Environment
Countries accounting for largest share of EU supply of CRMs 5/13/2019 Critical metals and minerals in Finland
• Finland has a good potential for CRMs LREE HREE • Production of Co, Pt, Pd and apatite • Li production by 2022 • PGE, Co, P, Nb, REE, Sb, Be, graphite, Sc, Ta, W, V, Li prospects • E.g. large pre-glacial bedrock areas (saprolite/saprock) in Northern Finland, with weathered horizon ~100 m in depth • Till and lithogeochemistry are good indicators for Production in Finland / Year 2018 Cobalt refining production: 12 874 t Cobalt mining production: 1 377 t LREE and HREE Platinum refining production: 1 804 kg Platinum mining production: 1 576 kg mineralizations Palladium refining production: 1 804 kg 5/13/2019 Palladium mining production: 1 157 kg Apatite concenctrate mining production: 989 073 t Li hydroxide production will start in 2022 (long term estimate 12 000 t/y) Exploration challenges
• Exploration is challenging in the northern and Arctic regions because of the complex glacial history • Large peat bog and tundra areas; pre-glacial weathered bedrock • Logistical problems, conservation and reindeer herding areas, and sensitive arctic nature restrict sampling & research • Social license to operate
Photo by M. Moilanen
5/13/2019 Indicator mineral method • Commonly used exploration method in glaciated terrains • Indicator minerals in glacial sediments indicate the presence of a mineralization • Indicators minerals: (a) visually and chemically distinct (b) sufficiently dense to be concentrated by gravity (c) chemically and physically resistant to survive preglacial weathering and glacial transport (d) more abundant than the actual ore minerals (ore minerals are also indicators!)
Indicator mineral fan (example): Horizontal and Ice flow vertical distribution of indicators in till
0.5 km 1.5 km 2.0 km
5/13/2019 Excavator sample (rectangle) = 20 kg Drilled sample (sphere) = 5-9 kg Commonly used indicator minerals (McClenaghan, 2013).
Commodity / Deposit Indicator minerals Chemical composition Average density (gcm-3) Typical size range (mm) 1 Diamond Cr-pyrope garnet (Mg,Fe)3(Al,Cr)2(SiO4)3 3.7 0.25-0.5
Eclogitic garnet (Fe++,Mg)3Al2(SiO4)3 4.0 0.25-0.5
Mg-ilmenite (Fe++,Mg)TiO3 4.7 0.25-0.5
Cr-diopside CaMg(Fe,Cr)Si2O6 3.3 0.25-0.5
Chromite (Fe++, Mg)(Cr,Al)2O4 4.8 0.25-0.5
Forsteritic olivine (Mg,Fe)2SiO4 3.3 0.25-0.5 Diamond C 3.5 0.25-0.5 Gold2 Gold Au 17.6 0.01-0.25
Scheelite CaWO4 6.0 0.01-0.25
Rutile TiO2 4.3 0.01-0.25 Sulphides >4.0 0.01-0.25 3 Magmatic Ni-Cu-PGE Cr-diopside CaMg(Fe,Cr)Si2O6 3.3 0.25-2.0
Forsteritic olivine (Mg,Fe)2SiO4 3.3 0.25-2.0
Enstatite (Mg,Fe)2Si2O6 3.2 0.25-2.0
Chromite (Fe++, Mg)(Cr,Al)2O4 4.8 0.25-2.0
Pentlandite (Fe,Ni)9S8 4.8 0.01-0.25
Pyrrhotite Fe(1-x)S (x=0-0.17) 4.6 0.01-0.25
Chalcopyrite CuFeS2 4.2 0.01-0.25
Pyrite FeS2 5.0 0.01-0.25 Platinum group minerals (PGM) >8.0 0.001-0.1 5/13/2019 Continues…
Continues… 4
VMS deposits Chalcopyrite CuFeS2 4.2 0.01-0.25 Galena PbS 7.4 0.01-0.25
Sphalerite (Zn,Fe)S 4.1 0.01-0.25
Pyrrhotite Fe(1-x)S (x=0-0.17) 4.6 0.01-0.25
Pyrite FeS2 5.0 0.01-0.25
Gahnite (Zn,Fe)Al 2 O4 4.3 0.25-2.0
Spessartine (Mn++,Fe)3Al2(SiO4)3 4.2 0.25-2.0
Staurolite (Fe++,Mg)2Al9(Si,Al)4O20 (O,OH)4 3.7 0.25-2.0 Pb-Zn deposits5 Galena PbS 7.4 0.01-2.0 (Mississippi Valley type) Sphalerite (Zn,Fe)S 4.1 0.01-2.0 6 Porphyry Cu deposits Sulphides > 4.0 0.25-2.0
Andradite Ca3Fe+++2(SiO4)3 3.9 0.25-2.0 Diaspore AlO(OH) 3.4 0.25-2.0
Barite BaSO4 4.5 0.25-2.0
Alunite KAl 3(SO4)2(OH) 6 2.7 0.25-2.0
Dravite NaMg3Al6(BO3)3Si6O18(OH)4 3.1 0.25-2.0
Apatite Ca5(PO4)3(OH,F,Cl) 3.2 0.25-2.0 7 W-Mo deposits Scheelite CaWO4 6.0 0.01-0.25
Wolframite (Fe,Mn)WO4 7.3 0.01-0.25 Sulphides >4.0 0.01-0.25 Bi minerals >6.0 0.01-0.25
References:
1. McClenaghan & Kjarsgaard (2007) 2. McClenaghan & Cabri (2011) 3 and 6. Averill (2011) 4. Averill (2001) 5. Oviatt et al. (2013) 7. McClenaghan et al. (2013)
5/13/2019
Indicator mineral workflow
Field work / Sampling Preconcentation Laboratory work Microscopy Mineral analysis
Efficient concentration of indicator minerals is crucial to Indicator mineral achieve statistically relevant results. fingerprinting based on quantitative composition, trace Indicator mineral methodology revisited for CRM exploration: element contents, INDIKA project. isotopic composition etc. 5/13/2019 Photo: Kari A. Kinnunen INDIKA Project
• Automated indicator mineral identification methods for the critical mineral exploration • European Regional Development Fund (ERDF) funded project (2016-2019) • Partners: Geological Survey of Finland (consortium leader), Lapland University of Applied Sciences, and University of Oulu • Companies: Oxford Instruments, Suomen Kaivosyrittäjät ry, and the Gold Prospectors Association of Finnish Lapland • Project Manager professor Pertti Sarala • Budget 420 000 €
• Development of an exploration concept for critical minerals based on: • Cost-effective techniques for indicator mineral concentration • Automated indicator mineral identification methods • Using new on-site geochemical and mineralogical analysis techniques • Increasing co-operation between research organizations, mineralogical laboratory facilities and companies in northern Finland
5/13/2019 INDIKA Work packages P. Sarala GTK
P. Sarala P. Sarala P. Sarala
Field testing and documentation • Development of a protocol & data transfer from the field Concentration techniques (field/laboratory) • Knelson Concentrator, goldhound, Wilfley table, panning, heavy liquids, hydroseparation, magnetic separations… Advanced on-site and laboratory analytical techniques • Mobile XRD, portable XRF, hyperspectrum imaging • FE-SEM-EDS (MLA), RAMAN, XRD, XRF, ICPMS Case studies • Sokli P-REE mineralization in Eastern Lapland • Mäkärä Au-REE target in Central Lapland • Rautuvaara Fe-Cu mine tailings area in Western Lapland
Piloting 5/13/2019 • A new exploration target in Vuolijoki, Eastern Finland Sampling Concentration Field work
Sieving
A. Taivalkoski
On-site analysis
Subsampling Photos P. Sarala P. Sarala Hanna Koskinen 2018: Maximum results already on the field: more flexibility in the 5/13/2019 MSc thesis on pXRD, exploration program & savings in the exploration budget. Validation in labroratory University of Oulu Laboratory & analytical work
Wilfley Table / Dry Screening: Original Sample Wet Screening Concentrate: Heavy Liquid Knelson 63-100 & 100-160 12 litres 2mm LIMS d=3.3 gcm-3 Concentrator µm
GTK
Sokli heavy mineral concentrate Frantz 0.3 A 63-100 microns NONMAG Sample prep / Mineral Grain count Vol-% 63-100 and 100-160 FESEM µm Monazite 1800 11.70 >3.3 gcm-3 Frantz 0.5 A Fe-oxide 1708 16.28 NONMAG Zircon 1666 11.45 Sample prep / Baddeleyite 877 6.69 FESEM Rutile_Ti-Ox 669 11.29 Epidote 651 17.92 Pyrochlore 529 4.12 Apatite 303 5.56 Test samples were used for optimization. Heavy mineral distribution Clinozoisite 228 6.39 into grain size, density and magnetic fractions was studied. Up to 300 Chlorite 129 0.41 Staurolite 84 2.34 times enrichment of indicators was achieved. Modal mineralogy Zirkelite 66 0.37 measurements were carried out by automated FE-SEM-EDS. Almandine 61 0.34 5/13/2019 Mg-Hornblende 54 1.10 Total 9226 100.00 Recognized indicator minerals
M. Lehtonen Indicator mineral Chemical Formula Mäkärä Au-REE target 2+ Allanite CaCe(Al2Fe )[Si2O7][SiO4]O(OH) • Zircon, monazite, apatite, allanite, xenotime Apatite Ca5(PO4)3(OH,F,Cl) • Zircon up to 30% in concentrate fractions, monazite Bastnäsite (Ce,La,Nd,Y)(CO3)F 3% Cerianite CeO2 3+ Cerite (Ce,La,Ca)9(Mg,Fe )(SiO4)3(SiO3OH)4(OH)3 Cobaltite CoAsS Sokli P-REE target 2+ Columbite (Fe ,Mg,Mn)Nb2O6 • Zircon, monazite, pyrochlore, baddeleyite, apatite, Monazite (Ce,La,Nd,Sm)(PO4) allanite, xenotime, zirkelite Pyrochlore Ca Nb O 2 2 7 • Pyrochlore up to 11% in concentrate fractions, Thorite Th(SiO4) W-rutile (W)TiO2 monazite 12%, zircon 21%, baddeleyite 8% Xenotime Y(PO4) Baddeleyite ZrO2 Rautuvaara tailings area Zirkelite (Ca,Th,Ce)Zr(Ti,Nb)2O7 • W-rutile, monazite, cobaltite, apatite, allanite, Zircon Zr(SiO ) 4 xenotime, zircon, baddeleyite, thorite • W-rutile up to 2% in concentrate fractions
5/13/2019 INDIKA: Results
• New, tested and documented method for CRM exploration • Piloting of the method at Vuolijoki 25.-26.6.2018 • Bedrock source for REE bearing surface boulders discovered • On-site analytical methods • Mineralogical information obtained already during the field work • Data needs to be validated in the laboratory • Future research opportunities • Field conditions challenging for sample processing and preparation > Mobile field laboratories needed • Indicator mineral concentration techniques • Several processing methodologies were tested and documented • Methodologies can be adapted to various P. Sarala exploration targets
5/13/2019 INDIKA: Future goals and opportunities • Increasing exploration activity in Finland for the CRMs • Service concept development • Creating new business opportunities • New local services • Developed methods applicapble also for ”traditional” minerals/metals exploration • Strengthening cooperation within R&D sector • Research institutes, universities, companies • Strengthening mineral potential mapping • New research technologies > Geological knowledge > New ore deposits • Using modern technology to discover raw P. Sarala materials needed for the modern technology.
5/13/2019 Thank you for your attention
For more information, please contact:
Pertti Sarala, Project manager [email protected]
Marja Lehtonen [email protected]
Anne Taivalkoski, Project secretary [email protected] http://www.gtk.fi/tutkimus/tutkimushankkeet/indika.html
5/13/2019