Norsk versjon
THE ORE DATABASE
Occurence 4018 - 011 Søve
(Object Id: 5739)
(Last updated: 20.03.2024)

Location
County: Telemark Municipality: Nome (4018)
Map 1:50000: Nordagutu (1713-4) Map 1:250000: Skien
Coordinate system: EU89-UTM Zone 32
East: 516234 m. North: 6571482 m.
Longitude: 9.2849090 Latitude: 59.2819480
Show on map

Resource
Resource Type: Special metals (Nb,Ta,Be,Li,Sc,REE) Resource Subtype: Niobium
Element(s): Nb Ta REE
Importance
Raw material meaning: Not Assessed (reg. 22.05.2015)

Resources and production
Activity: Mining Reserves:
Operating method: Open pit and underground mining Historical production: 1150 thousand tons


Products
Element/product Crude ore grade or quality Reg. date
Nb 2800 ppm 20.03.2024

Operations
From - To Activity Comments
1951 - 1965 Regular production Company/Institution :Norsk Bergverk AS

Mineralization
Era: Paleozoic Period: Cambrian
Genesis: Intrusive breccia/diatreme Form:
Main texture: Structureless Min. distribution: Disseminated (<20 % ore minerals)
Main grain size: Fine grained (< 1 mm) Main alteration: Carbonate alteration
Strike/Dip: Direction:
Plunge:
Stratigraphic classification of host rock
Era: Period:
Province:
Geotec.unit:
Tectonic complex:
Igneous complex:
Group: Formation:

Mineralogy
Relationship Mineral Amount
Gangue mineral Calcite Major mineral (>10%)
Gangue mineral Mica Subordinate mineral (1-10%)
Gangue mineral Apatite Subordinate mineral (1-10%)
Ore mineral Pyrochlore Major mineral (>10%)
Ore mineral Synchysite Accessory mineral (<1%)
Ore mineral Bastnäsite Accessory mineral (<1%)
Ore mineral Monazite Accessory mineral (<1%)
Ore mineral Parisite Accessory mineral (<1%)

Information(s) in free text format
Free text
Fen is an early Cambrian silicate-carbonatite composite complex, which has a diameter of 5 km. It consists of a number of different intrusive to subvolcanic lithologies, including calcio- and ferrocarbonatites and various alkaline silicate rocks. The ferrocarbonatites are rich in ankerite and dolomite and contain Nb-, REE- and Th-rich minerals. In the eastern part of the complex, a red-colored carbonate- and oxide-rich rock unit occurs that is termed "rødbergite" (red rock). The red color is caused by finely dispersed hematite. Locally, the hematite is concentrated in dykes and veins and 1 mill t. of hematite ore was exploited by the Fen iron mines between 1657 until 1929. The rødberg rocks are rich in thorium and REE and resources are estimated to contain 170 000 t with 0.2 % Th and about 1 % REE (LREE). The calciocarbonatites (søvites) contain calcite, pyrochlore, biotite, REE-F-carbonates and monazite and the state-owned company AS Norsk Bergverk produced 1.15 mill t. of Nb-ore between 1953-1965 in the Søve mines, which gave 4100 t of Nb2O5. The pyrochlore is mainly concentrated along the margin of the carbonatite, but also related to breccia zones crosscutting the central part of the intrusion.

Bibliography:
From NGU's Reference Archive:
Bergstøl, Sveinung; Svinndal, Sverre , 1960
Description of mines and deposits. Søve Niobium Mine, Fen area.
;Norges geologiske undersøkelse;EKSKURSJONSGUIDE; TIDSSKRIFTARTIKKEL;NGU; No.212m;16-26 pages

Bergstøl, Sveinung; Svinndal, Sverre , 1960
The carbonite and per-alkaline rocks of the Fen area. Petrology.
;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.208;99-105 pages

Sæther, Egil , 1957
The alkaline rock province of the Fen area in southern Norway.
;ARTIKKEL;Det Kongelige Norske Videnskabers Selskabs Skrifter; No.1;150 s. pages
Abstract:
An account is given of the field relationships, petrography, and mode of formation of alkaline silicate and carbonate rocks in the Cambro-Silurian Fen area in Telemarken, southwestern Norway. The Fen complex lies in Archean gneiss and gneissose granite and consists of the following rocks: granitic breccia; fenite (syenite); vipetoite, melteigite, ijolite, urtite (mafic alkalic rocks); damtjernite (hypabyssal rock); soevite (calcite rock); rauhaugite (ankerite rock); roedbergite or red rock (clacite-ankerite-hematite rock); and some dike rocks. Chemical rock and mineral analyses and spectrochemical analyses of oxide and sulfide minerals are presented, and optical data are given for many minerals. Substance transfers are computed for various metasomatic rock transformations in the area. Petrofabric diagrams of carbonatites are presented and interpreted. Genesis of the rocks is ascribed to two magmas poor in silica and rich in alkali metals, calcium, and carbon dioxide. Two separate cycles are established, each of which involved eruption of a mafic magma with subsequent very extensive hydrothermal activity (alkali metasomatism and carbonatization). The Fen area is compared with Alnø in Sweden, its close counterpart.

Lie, Anders; Østergaard, Claus , 2011
The Fen carbonatite complex, Ulefoss, South Norway. Results and conclusions from preliminary microscope and microprobe studies
;21st NORTH;RAPPORT;35 pages

Lie, Anders; Østergaard, Claus , 2011
The Fen carbonatite complex, Ulefoss, South Norway. Summary of historic work and data
;21st NORTH;RAPPORT;47 pages

Andersen, Tom , 1983
Iron ores in the Fen central complex, Telemark (S.Norway): Petrography, chemical evolution and conditions of equilibrium
;Norsk geologisk forening;TIDSSKRIFTARTIKKEL;Norsk geologisk tidsskrift; No.63 (2/3);73-82 pages
Abstract:
Hydrothermal iron ores from the Fen central complex may be classified according to their mineral assemblages as primary (magnetite +- pyrite +- anatase + calcite) or secondary (hematite +- goethite + calcite +- dolomite). Primary ores equilibrated between the hematite-magnetite and magnetite-pyrite-pyrrho- tite buffers, at temperatures below 600°C. Alteration to form the secondary parageneses took place above the hematite-magnetite buffer, probably at lower temperature.

Fieldsamples
Sample No. Sample type Miscellanrous
95394 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
95395 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
95397 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
95398 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
95399 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
95400 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
95401 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
95402 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
95403 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
95404 Bedrock
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
NB! All analyse values are shown at the end of the printout.:


Analyse Results
from
Deposit Area 4018 - 011 Søve

Element analyses

( *=parts pr. million, #=parts pr.billion, Negative values means below detection limit value.)
Sample No. Sample Type Co* Ni* Ba* Sn* Ga* V* Cr*
95394 Bedrock 10 730 1 4.40 133 21
95395 Bedrock 11 17301 7 8.40 89 103
95397 Bedrock 29 53 212 5 11.80 151 123
95398 Bedrock 16 2073 1 10.40 134 116
95399 Bedrock 14 581 2 1.80 121
95400 Bedrock 4 62 0.50 11
95401 Bedrock 8 916 0.60 83
95402 Bedrock 7 6941 6.90 77
95403 Bedrock 13 642 1.60 18 21
95404 Bedrock 5 83 2 2.80 28 41
------------------
Sample No. Th* U* W* Rb* Sr* Y* Zr* Nb* Ta*
95394 17.80 1.30 3.0 3920.7 58.3 259 59.50 6.90
95395 782.30 3.70 5 3.2 1885.1 116.8 116 706.30 12.40
95397 1080.10 22.90 12 1.0 304.0 366.5 177 840.80 3.70
95398 1470.60 3.40 11 0.5 140.2 263.6 175 667.80 0.40
95399 19.30 0.90 1.0 3789.7 69.3 74 46.00 4.60
95400 63.70 0.80 1 0.3 3800.9 24.8 50 2735.90 10.70
95401 28.60 113.60 6.0 4523.4 66.3 17 328.60 81.30
95402 67.00 104.80 1 27.8 2938.1 138.9 365 421.50 58.30
95403 98.20 18.70 1 1.3 5147.8 83.6 64 821.50 6.00
95404 106.80 5.70 1 0.5 430.8 46.1 13 302.90 3.10
------------------
Sample No. Cs* La* Ce* Pr* Nd* Sm* Eu* Gd* Tb*
95394 0.30 269.50 527.20 60.24 218.50 32.87 9.36 24.83 2.68
95395 0.80 1516.20 2906.30 338.52 1269.70 237.85 64.87 137.05 11.00
95397 432.40 1066.50 163.27 808.70 231.68 54.55 148.03 15.09
95398 0.10 1897.60 6680.90 1111.09 5046.40 546.73 94.51 163.71 10.31
95399 262.60 544.40 67.23 256.60 40.83 11.77 31.02 3.41
95400 137.80 313.40 38.75 140.50 21.92 5.92 14.93 1.50
95401 0.20 228.80 500.00 61.95 239.00 38.52 11.10 28.68 3.27
95402 0.20 541.90 1163.50 145.48 537.10 82.08 22.62 59.80 6.87
95403 0.30 1066.70 1778.80 209.41 813.20 139.91 31.32 62.38 4.51
95404 3289.60 4894.60 448.13 1334.30 116.53 14.30 56.96 3.49
------------------
Sample No. Dy* Ho* Er* Tm* Yb* Lu* Be* Hf*
95394 12.82 1.93 4.89 0.61 3.70 0.50 1 2.00
95395 40.77 4.15 9.04 1.41 9.63 1.23 2 3.10
95397 70.77 11.10 27.45 3.90 23.59 3.27 24 9.40
95398 44.92 5.62 15.73 2.22 13.43 1.79 9 2.30
95399 15.96 2.35 5.44 0.65 3.59 0.46 0.50
95400 6.40 0.96 2.14 0.25 1.28 0.15 0.90
95401 16.29 2.23 5.30 0.66 4.25 0.47 0.50
95402 32.95 5.00 12.00 1.47 8.21 1.06 3.50
95403 18.87 2.20 5.72 0.88 5.89 0.81 0.90
95404 12.41 0.99 2.13 0.32 2.28 0.26

Oxide analyses

( All values are in % )
Sample No. Sample Type SiO2 Al2O3 TiO2 Fe2O3 MnO MgO Na2O
95394 Bedrock 2.08 0.32 0.18 6.30 0.22 2.80 0.13
95395 Bedrock 5.02 1.67 0.71 16.49 1.83 10.36 0.11
95397 Bedrock 18.35 4.01 0.54 15.16 0.34 2.60 0.05
95398 Bedrock 2.05 0.71 0.07 90.39 0.54 0.54
95399 Bedrock 0.65 0.27 0.17 5.61 0.18 2.03 0.03
95400 Bedrock 0.75 0.02 3.42 0.60 17.06 0.01
95401 Bedrock 1.39 0.52 0.25 4.10 0.23 2.96 0.03
95402 Bedrock 9.73 2.47 0.56 5.58 0.35 6.09 0.08
95403 Bedrock 0.98 0.38 0.02 8.40 0.73 7.49 0.03
95404 Bedrock 1.47 0.58 0.01 1.98 0.32 0.84
------------------
Sample No. K2O P2O5 Loss Sum
95394 0.06 4.26 35.00 51.00
95395 0.07 0.24 35.70 72.00
95397 0.01 0.63 24.70 66.00
95398 0.02 0.67 0.30 95.00
95399 0.03 3.35 37.20 50.00
95400 4.16 40.70 67.00
95401 0.20 3.67 37.80 51.00
95402 1.52 15.70 19.80 62.00
95403 0.04 11.26 27.60 57.00
95404 0.35 40.90 46.00


The fact sheet was created on 28.03.2024

Questions or comments regarding the fact sheet can be emailed to:
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