Rare earth elements (REE) in two long drill-cores from the Fen Carbonatite Complex, Telemark, Norway : revised edition
NGU-RAPPORT
2019.008 rev.ed.
Publikasjonstype
Utgivelsesår
2023
ISSN
0800-3416
Prosjektnr
379500
Summary
Rare Earth Elements (REE) are metals that are classified as critical for the European industry. They are
fundamentally important in the manufacturing of High-tech and green technology products. Today
almost the total world REE-mining is controlled by China. REE deposits in Europe are few and none of
them are in production. Fe-dolomite carbonatite (“rauhaugites”) in the Fen Carbonatite Complex in
Telemark, Norway, has for some years been known to host abundant REE-minerals. The knowledge of
this rock type has, however, been limited to the near surface environment. In 2017 the Ministry of Trade,
Industry and Fisheries funded a reconnaissance core-drilling program to test the continuation of the Fedolomite carbonatite at depth. Two rock cores, 1001 and 716 metres long, were recovered at the drillsites, LHKB-1 (near Fen old school) and LHKB-2 (east of Søve) respectively. Core LHKB-1 consists
almost only of Fe-dolomite carbonatites down to 1001 metres depth. Core LHKB-2 also consists of Fedolomite carbonatite from top to bottom, but cross-cutting damtjernite (a lamprophyric rock) occur in
some intervals. Scattered REE-mineralizations are abundant in both drill-cores. Rare Earth Elementminerals are REE-fluorocarbonates (bastnaesite, parisite-synchysite), and subordinate REE-phosphate
(monazite). The LHKB-2 core is generally richer in REE (median TRE2O3 1.70 wt%) than the LHKB-1
(median TRE2O3 1.08 wt%). The thorium content is low (median 181.5 and 128.5 ppm in LHKB-1 and 2
respectively) in these Fe-dolomite carbonatites compared to the Fen rødbergite. Geological,
hyperspectral and geochemical analyses of these two-reconnaissance drill-cores demonstrates that the
REE-bearing Fe-dolomite carbonatites extend at least down to a depth of 1000 metres. An industrial
exploration program of the Fen Complex should be considered. This report with appendices presents all
chemical and hyperspectral data available from these two reconnaissance cores, and thus serves as an
excellent basis for competent industry to plan an eventual exploration program.
fundamentally important in the manufacturing of High-tech and green technology products. Today
almost the total world REE-mining is controlled by China. REE deposits in Europe are few and none of
them are in production. Fe-dolomite carbonatite (“rauhaugites”) in the Fen Carbonatite Complex in
Telemark, Norway, has for some years been known to host abundant REE-minerals. The knowledge of
this rock type has, however, been limited to the near surface environment. In 2017 the Ministry of Trade,
Industry and Fisheries funded a reconnaissance core-drilling program to test the continuation of the Fedolomite carbonatite at depth. Two rock cores, 1001 and 716 metres long, were recovered at the drillsites, LHKB-1 (near Fen old school) and LHKB-2 (east of Søve) respectively. Core LHKB-1 consists
almost only of Fe-dolomite carbonatites down to 1001 metres depth. Core LHKB-2 also consists of Fedolomite carbonatite from top to bottom, but cross-cutting damtjernite (a lamprophyric rock) occur in
some intervals. Scattered REE-mineralizations are abundant in both drill-cores. Rare Earth Elementminerals are REE-fluorocarbonates (bastnaesite, parisite-synchysite), and subordinate REE-phosphate
(monazite). The LHKB-2 core is generally richer in REE (median TRE2O3 1.70 wt%) than the LHKB-1
(median TRE2O3 1.08 wt%). The thorium content is low (median 181.5 and 128.5 ppm in LHKB-1 and 2
respectively) in these Fe-dolomite carbonatites compared to the Fen rødbergite. Geological,
hyperspectral and geochemical analyses of these two-reconnaissance drill-cores demonstrates that the
REE-bearing Fe-dolomite carbonatites extend at least down to a depth of 1000 metres. An industrial
exploration program of the Fen Complex should be considered. This report with appendices presents all
chemical and hyperspectral data available from these two reconnaissance cores, and thus serves as an
excellent basis for competent industry to plan an eventual exploration program.
Forfattere
Coint, Nolwenn
Dahlgren, Sven
Kommune
NOME
Fylke
TELEMARK
Tilgjengelig
NGU-biblioteket
Prosjekt
Karakterisering og ressursevaluering i Fensfeltet