Focus 5 2023 - Rare earth minerals

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REE rich core shows green-gold spots on a brown stone wih white spots.
REE-mineralisation from the Fen carbonatite complex. Photo Sven Dahlgren.

The fifth focus sheet of 2023 is about rare earth minerals in Norway and is written by Nolwen Coint.

While Norway has no active mine of REE, resources exist associated with a diversity of rock-types, including a carbonatite complex (Fen), alkaline and per-alkaline intrusions (Kodal, Sæteråsen- in the Oslo Rift; Misværdalen- in Caledonian nappe), pegmatites (Gloserhei –in Sveconorwegian basement), REE-enriched granites (Høgtuva, Tysfjord) and a hydrothermal-metasomatic deposit (Biggejavri).

The largest REE deposit in Norway, the Fen complex in southern Norway is a 2.8 km-large intrusion dominated by three types of carbonatites and subordinate alkaline rocks. While both the rødberg (hematite-calcite rock) and the Fe-dolomite carbonatite are enriched in REE, only the latter is considered for exploitation.

High Th content in the rødberg makes it less suitable for the industry at the moment. The Fe-dolomite carbonatite extends at least 1 km down, based on two long cores fnanced by the Norwegian government in 2017 (Coint and Dahlgren, 2019).

Associated REE mineralization is dominated by Light Rare Earth Elements (LREE), Ce being the most abundant element. Bastnaesite, a REE fuorocarbonate (CeCO3F) and monazite, a LREE-rich phosphate (CePO4), are the two main REE-bearing minerals while synchysite (Ca(Ce)(CO3) 2F) and parasite (CaCe2(CO3)3F2) are subordinate. A resource estimate conducted on a small portion of the Fe-dolomite carbonatite, based on tightly spaced drill-cores, approximates 18.3 Mt with an average grade of 1.6 % TREO with a 1.2 % TREO cut of, according to REE minerals.

The distribution of the REE mineralization and calculation of inferred resources is under investigation with a new drilling program planned throughout 2022, which you can read more about at rareearthsnorway.com.

A second potential source of REE in the country is apatite of magmatic origin, where REE could be a byproduct from the extraction of phosphorus. Apatite has never been extracted as a source of REE in Norway as of today, but prospection is ongoing in the Bjerkreim-Sokndal layered intrusion, where resources are estimated at 0.064 Mt TREO. Apatite there is associated with V-rich magnetite and ilmenite. Resources of REE associated with the Kodal deposit, in the Oslo Rift, are estimated to 0.16 Mt TREO (Decrée et al., 2022).

References

Reports and publications:

Coint, N. and Dahlgren, S. (2019). Rare earth elements (REE) in two long drill-cores from the Fen Carbonatite Complex, Telemark, Norway.

NGU report, Geological Survey of Norway (NGU). 2019.008: 36. Decrée, S., N. Coint, V. Debaille, G. Hagen-Peter, T. Leduc and H. Schiellerup (2023). “The potential for REEs in igneous-related apatite
deposits in Europe.” Geological Society, London, Special Publications 526(1): SP526-2021-2175.

Goodenough, K. M., J. Schilling, Jonsson, E., Kalvig, P., Charles, N., Tuduri, J., Deady, E. A., Sadeghi, M., Schiellerup, H., Muller, A., Bertrand, G., Arvanitidis, N., Eliopoulos, D. G., Shaw, R. A., Thrane, K.,
Keulen, N. (2016). "Europe's rare earth element resource potential: An overview of REE metallogenetic provinces and their geodynamic setting." Ore Geology Reviews 72: 838-856.

Ihlen, P. M., Schiellerup, H., Gautneb, H., and Skår, Ø., 2014. Characterization of apatite resources in Norway and their REE potential — A review. Ore Geology Reviews, 58: 126–147.

Dahlgren, S., 2019. REE mineralization in the Fen Carbonatite Complex, Telemark, Norway – A world class exploration target for the Hi-Tech and “Green-shift” Industry? Buskerud Telemark Vestfold
County Council, report 2019-01, 86p.

Ongoing projects at NGU:
Formation of phosphate deposits in Norway- Nolwenn Coint and Eduardo Mansur Critical metals (P-REE) potential in the southern part of the Oslo rift-Vestfold-Telemark – Nolwenn Coint and Eduardo Mansur

For more information, please contact

Sven Dahlgren, Geological Advisor,
Vestfold and Telemark County council
sven.dahlgren@vtfk.no