Aitolampi – Graphite
The Pitkäjärvi and Aitolampi graphite prospects were discovered by Beowulf in 2016 and are eastern extensions of known old graphite workings from when graphite prospecting was undertaken many years ago. The project area is located in Eastern Finland, approximately 40km southwest of the well-established mining town of Outokumpu.
Infrastructure in the area is excellent, with good road access and the availability of high voltage power. Beowulf’s 100% owned subsidiary Company, Grafintec Oy, holds an Exploration Permit, Pitkäjärvi 1, which covers 999.7ha. A three year extension application has been submitted to Tukes on Oct 15, 2020.
Business Finland has been granted Euros 10 million funding for a project titled “BATCircle – the development of a Finland-based Circular Ecosystem of Battery Metals”, where Grafintec Oy is part of battery supply chain development and recycling in Finland. The BATCircle project is part of the European Union (EU) Strategic Energy Technology Programme, where Finland, under the leadership of Aalto University and Outotec, will coordinate research into battery applications and recycling.
During 2019, the Grafintec team produced an upgraded Mineral Resource Estimate (“MRE”) for the Aitolampi project, with a global Indicated and Inferred Mineral Resource of 26.7 million tonnes at 4.8 per cent Total Graphitic Carbon for 1,275,000 tonnes of contained graphite, reported in accordance with the JORC Code, 2012 edition.
MRE for Aitolampi as at 28 August 2019
|Classification||Mt||TGC %||S %||Density (t/m3)||Contained graphite (kt)|
|Indicated + Inferred||26.7||4.8||4.7||2.81||1,275|
Note: The Mineral Resource was estimated within constraining wireframe solids defined within the logged graphitic schist host unit and nominally above a 3% TGC cut-off. The Mineral Resource is reported from all blocks within these wireframe solids Differences may occur due to rounding.
The Aitolampi graphite schists occur on a fold limb within a high metamorphic quartz-feldspar-biotite gneiss (QFB) host rock and are coincidental with an extensive electro-magnetic (EM) anomaly defined by an airborne survey undertaken by Geological Survey of Finland (GTK). Beowulf has carried out its own additional geophysical survey, utilising Slingram horizontal loop electromagnetic (HLEM) and other geophysical methods, to provide a rapid andinitial assessment of the project for potential subsurface graphite mineralisation. The results of the surveys were very encouraging and metallurgical test-work carried out on composited grab samples. Aitolampi was quickly considered by Beowulf’s geologists to be the most prospective forfollow-up exploration by drilling.
In 2019, the Company announced an upgraded JORC compliant global Indicated and Inferred Mineral Resource of 26.7 million tonnes at 4.8 per cent TGC for 1,275,000 tonnes of contained graphite. The Mineral Resource was estimated by CSA Global PTY Ltd (CSA Global) of Australia.
The western zone is higher grade with a reported Indicated and Inferred Mineral Resource of 9.8 million tonnes (Mt) at 5% TGC for 490,000 tonnes of contained graphite. The Eastern Zone has an Indicated and Inferred Mineral Resource of 9.5 Mt at 4.1% TGC for 388,000 tonnes of contained graphite.
Aitolampi Resource Estimate by mineralisation zone
|Zone||Classification||Mt||TGC %||S %||Density (t/m3)||Contained graphite (kt)|
|Indicated + Inferred||17.2||5.2||4.8||2.80||887|
|Indicated + Inferred||9.5||4.1||4.5||2.82||388|
|TOTAL||Indicated + Inferred||26.7||4.8||4.7||2.81||1,275|
Note: The Mineral Resource was estimated within constraining wireframe solids defined within the logged graphitic schist host unit and nominally above a 3% TGC cut-off. The Mineral Resource is reported from all blocks within these wireframe solids. Differences may occur due to rounding.
All reported mineralisation is contained within the two graphitic zones, the eastern and western lenses. The drilling has confirmed a mineralised strike length of at least 525m for the eastern zone and 530m for the western zone. Mineralisation for both zones remains open along strike and at depth. A number of EM conductive zones still remain untested by drilling.
Three composited quarter drill core samples of approximately 10kg each were dispatched in 2017 to SGS Minerals Services in Canada for metallurgical test-work. The following results were achieved:
- Superior metallurgical response from all three samples compared with grab samples from outcrops analysed previously
- The process flowsheet used was simple, yet proved to be very efficient
- The combined grades ranged from 96.8% to 97.5% Ct across the three samples
- All three samples responded similarly in terms of concentrate grades of the various size fractions
- The -400 mesh size fractions also produced high grades ranging from 95.0% to 97.8% per cent Ct
|Flake Size||Size in Microns||Size in Mesh||% Mass Distribution|
|Large||180 to 300||80 to 50||17||12.2||13.4|
|Medium||150 to 180||150 to 80||30||26.8||29.2|
|Fine||< 106||< 150||51.4||60.4||56.8|
|Ct Combined Concentrate||96.8%||97.20%||97.50%|
|% Open Circuit Graphite Recovery||87.30%||77.80%||91.40%|
Concentrates from the SGS testwork conducted in 2017 were sent to ProGraphite Gmbh (ProGraphite) for purification and characterisation tests. ProGraphite specialises in the processing and evaluation of graphite materials. Acid and alkaline purification tests were undertaken and the following results were achieved:
- Alkaline purification produced 99.86 per cent Total Carbon (“C(t)”) for +100-mesh concentrate and 99.82 per cent C(t) for -100-mesh concentrate.
- Results from acid purification were also promising and reached 99.6 per cent C(t) for the +100-mesh and 99.41 per cent C(t) for the -100-mesh concentrate.
- The alkaline and acid purification results indicate that, with some process optimisation, Aitolampi concentrates may meet the purity specification of 99.95 per cent C(t) required for the lithium ion battery market.
- Aitolampi graphite shows high crystallinity, with the degree of graphitisation measuring approximately 98 per cent, which is almost perfect crystallinity, an important prerequisite for high tech applications, such as lithium ion batteries.
- Volatiles are low, which is an attractive product attribute in many applications, including refractories, lubricants, crucibles, and foundries.
- Specific Surface Area (SSA) is comparable to that of high-quality flake graphite from China.
- Oxidation behaviour is comparable with Chinese graphite of the same flake size, used for refractories, and other high temperature applications.
ProGraphite has recently also completed a purification and spheronisation programme using concentrates from Aitolampi. In addition, battery tests on Aitolampi purified micronized and purified spheronised graphite are being completed at the Battery Materials Laboratory in Kokkola, Finland.