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THE ORE DATABASE
Deposit Area 937 - 010
(Last updated 08.okt.2025)

Name of Deposit Area : Flåt
(Object Id : 0937,010,00,00)
Location
County : Aust-Agder (09) Municipality : Evje og Hornnes (0937)
Map 1:50000: Evje (1512-3) Map 1:250000: Mandal
Marking point: Longitude: 7.8707160 Latitude: 58.5984440
EU89-UTM Zone 32 (Coordinates IS confirmed)
X-coord: 434368 m. Y-coord: 6495892 m.
Commodity
Main Type: Ferroalloys (Cr,Ni,Co,V,Mo,W) Sub Type: Nickel
Element(s): Ni Cu Co
Production
Activity: Mining Reserves:
Prod. method: Open pit and underground mining Production: 2700 thousand tons
Prod. status: Disused, closed Volume of dump: 1000000 m3

Importance
Public: Not Assessed (reg. 20.03.2017)
Economical: Significant , (Confirmed 19.mar.2007 by Morten Often)
Historical: Yes , (Confirmed 16.feb.2005 by Havard Gautneb)

Products
Element/product Crude ore grade or quality
CO 0,015
CU .48 %
NI .72 %
P 4 %

Operations
From - To Activity Comments
Geophysics
1872 - 1946 Regular production
1933 - 1944 Core drilling
1990 - 1991 Geology

Mineralization
Era: Proterozoic Period: Mesoproterozoic
Dating: Method:
Genesis: Orthomagmatic formation Form: Lens
Main texture: Structureless Min. distribution: Semi-massive (20-50 % ore minerals)
Main grain size: Medium grained (1-3 mm) Main alteration: Chloritisation
Strike/Dip: 10 / 45 Direction:
Plunge:
Stratigraphic classification of host rock
Era: Proterozoic Period: Mesoproterozoic
Province: South Norwegian Basement Province
Geotec.unit: Setesdal-Hallingdal Complex
Tectonic complex:
Igneous complex: Evje Amphibolite Complex
Group: Formation:

Mineralogy
Relationship Mineral Amount
Gangue mineral Biotite Major mineral (>10%)
Gangue mineral Amphibole Major mineral (>10%)
Gangue mineral Chlorite Subordinate mineral (1-10%)
Gangue mineral Apatite Subordinate mineral (1-10%)
Gangue mineral Pyroxene Accessory mineral (<1%)
Ore mineral Pyrrhotite Major mineral (>10%)
Ore mineral Pentlandite Subordinate mineral (1-10%)
Ore mineral Chalcopyrite Subordinate mineral (1-10%)
Ore mineral Pyrite Subordinate mineral (1-10%)
Ore mineral Millerite Accessory mineral (<1%)
Ore mineral Violarite Accessory mineral (<1%)

Lithology:
Relationship Rock Origin
Unknown Mykleås amphibolite Intrusive
Original rock :Diorite
1000 mill. years;..Method:Rb/Sr
Metamorphic facies :Amphibolite
Host rock Flåt diorite Intrusive
Original rock :Quartz diorite
950 mill. years
Metamorphic facies :Amphibolite

Structures
Location: Type: Orientation(360 gr.): Relation to min.:
Unknown Shear plane Strike/Dip :10 / 80 Syn-mineralisation ;...Effect :None
Unknown Fault plane Strike/Dip :10 / 35 Post-mineralisation ;...Effect :Controls

Information(s) in free text format
Free text
The Flåt nickel-copper deposit is associated with a plagioclase-rich diorite, located on the western margin of a larger, early Sveconorwegian complex, the Iveland-Gautestad metagabbroic complex. The Flåt ore was was mined from 1844 as a copper deposit, from 1872 as a copper-nickel deposit. The mine was worked intensively during WW II and was closed in 1946. Total production is estimated to have been 2.7 Mt, containing 20,200t Ni, 14,500t Cu and 2,400t Co. The deposit forms a pencil-shaped body underlain by an irregular body of gneiss. Typical ore contains 12-13% sulphide, 75% silicates, 8% magnetite and 4% apatite. The major sulphides are pyrite, pyrrhotite, pentlandite and chalcopyrite.

Bibliography:
From NGU's Reference Archive:
Bjørlykke, Harald , 1947
Flåt nickel mine.
;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.168b;1-39 + fo pages

Barth, Tom F. W. , 1947
The Nickeliferous Iveland-Evje amphibolite and its relation.
;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.168a;1-71 + fo pages
Abstract:
The pre-Cambrian nickelferous meta-norite at Iveland-Evje represents an amphibolite body entirely surrounded by gneissous granite and augen genisses. More than 90% of the amphibolite body is made up with schistose or gneissic rocks in most of which alternating dark and light layers have developed through the combined effect of recrystallization and internal differential movements. So thorough has been the re-working of the material that the determination of the nature of the original rock is utterly impossible. The conclusion that at least part of this rock was norite is based entirely on circumstancial evidences, such as the association with nickel ore, and the petrographical analogy of certain facies of the Evje rock with nickelferous norite elsewhere. The individual dark and light bands, although sharply separated, are composed of exactly the same kinds of mineral: Plagioclase has the same chemical composition, and hornblende and biotite exhibit the same optical constants in both bands; only the relative proportions of the minerals differ radically. In some places banding is not well developed, but light and dark constituents have separated in concretionary patches.

Fieldsamples
Sample No. Sample type Miscellanrous
FLÅT 06-1 Hand specimen
Sampler :M. Often
Comment :Diorite, with cp and po. From "Koparhola".
No. of registrated element analyses = 1
FLÅT 06-2 Hand specimen
Sampler :M. Often
Comment :Diorite, with cp and po. From "Koparhola".
No. of registrated element analyses = 1
FLÅT 06-3 Hand specimen
Sampler :M. Often
Comment :Diorite, with sulphides.
No. of registrated element analyses = 1
FLÅT 06-4 Hand specimen
Sampler :M. Often
Comment :Diorite, with sulphides.
No. of registrated element analyses = 1
Flåt01 Dump
Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2
Comment :Massive, fine grained pyrrhotite-chalcopyrite
No. of registrated element analyses = 1
Flåt02 Dump
Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2
Comment :Net-textured chalcopyrite-pyrrhotite in diorite
No. of registrated element analyses = 1
Flåt03 Dump
Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2
Comment :Pyrrhotite-chalcopyrite dissemination/net-textured in diorite
No. of registrated element analyses = 1
Flåt04 Dump
Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2
Comment :Massive, fine grained pyrrhotite-chalcopyrite
No. of registrated element analyses = 1
Flåt05 Dump
Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2
Comment :Weak dissemination of pyrrhotite+chalcopyrite in metagabbro
No. of registrated element analyses = 1
Flåt06 Dump
Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2
Comment :Net-textured pyrrhotite-chalcopyrite, fine grained (skeide-dump)
No. of registrated element analyses = 1
Flåt07 Dump
Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2
Comment :Chalcopyrite aggregates in vein and chalcopyrite-pyrrhotite dissemination in diorite
No. of registrated element analyses = 1
Flåt08 Bedrock
Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2
Comment :Semi-massive/massive pyrrhotite+chalcopyrite in diorite
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Analyse Results
from
Deposit Area 937 - 010 Flåt

Element analyses
( *=parts pr. million, #=parts pr.billion, Negative values means below detection limit value.)
Sample No. Sample Type Cu* Zn* Pb* Co* Ni* Ag* Au#
FLÅT 06-1 Hand specimen 49706 293 54 214 5398 20.0 121.0
FLÅT 06-2 Hand specimen 9962 84 33 253 17936 6.3 170.0
FLÅT 06-3 Hand specimen 3080 128 28 140 4265 2.0 19.0
FLÅT 06-4 Hand specimen 3721 101 66 102 5209 2.0 30.0
Flåt01 Dump 2180 54 30 675 2 1.6 31.0
Flåt02 Dump 22000 206 64 342 11.9 92.0
Flåt03 Dump 1225 170 41 275 .9 10.0
Flåt04 Dump 5210 100 40 587 2 3.0 40.0
Flåt05 Dump 1790 213 50 229 .9 20.0
Flåt06 Dump 10550 126 19 2110 6.6 185.0
Flåt07 Dump 6080 112 32 324 3.4 68.0
Flåt08 Bedrock 1360 129 37 915 1 .9 11.0
------------------
Sample No. Pt# Pd# As* Cd* Ba* Mo* Sn* Sb* Bi*
FLÅT 06-1 14.0 9.0 5 2.2 1.00 3
FLÅT 06-2 66.0 15.0 2.00
FLÅT 06-3 16.0 3.0
FLÅT 06-4 8.0 -2.0 -.5
Flåt01 88.0 92.0 2 .1 100 4.52 1 0 3
Flåt02 65.0 15.0 2 .7 160 2.10 4 0 3
Flåt03 13.0 14.0 1 .1 120 1.72 4 0 1
Flåt04 97.0 67.0 1 .3 190 2.18 3 0 2
Flåt05 31.0 12.0 2 .4 390 1.27 5 0 1
Flåt06 160.0 33.0 2 .3 10 3.63 2 0 3
Flåt07 2.5 6.0 3 .3 540 1.58 3 0 1
Flåt08 13.0 60.0 2 .2 130 2.99 2 0 2
------------------
Sample No. Se* Ga* Ge* In* S% V* Cr* Mn* Fe%
FLÅT 06-1 7.70 101 241 208 16.07
FLÅT 06-2 13.70 100 314 226 24.94
FLÅT 06-3 3.50 66 7.19
FLÅT 06-4 3.60 91 92 10.87
Flåt01 35.00 4.56 0.33 0.03 21.40 135 231 796 42.20
Flåt02 17.00 13.15 0.23 0.16 189 314 1330 23.40
Flåt03 10.00 16.75 0.22 0.11 501 1825 1810 26.90
Flåt04 30.00 6.46 0.33 0.06 17.00 147 216 711 36.90
Flåt05 7.00 16.20 0.20 0.15 401 750 1755 20.80
Flåt06 27.00 10.65 0.25 0.05 20.00 183 623 1000 30.80
Flåt07 7.00 16.75 0.29 0.11 215 392 1035 21.40
Flåt08 23.00 9.46 0.25 0.06 15.05 199 319 1135 30.60
------------------
Sample No. Th* U* W* Rb* Sr* Y* Zr* Nb* Ta*
FLÅT 06-1 4.00 1.00 62.0
FLÅT 06-2
FLÅT 06-3 128.0
FLÅT 06-4 94.0
Flåt01 0.59 0.20 1 3.1 62.0 6.9 4 6.80 0.37
Flåt02 3.87 0.90 0 22.0 512.0 20.4 37 12.70 0.70
Flåt03 1.91 0.90 1 4.1 100.5 17.0 25 22.30 1.25
Flåt04 1.00 0.30 0 8.1 447.0 10.6 8 7.20 0.43
Flåt05 2.98 1.50 1 17.6 411.0 22.8 29 22.70 1.20
Flåt06 1.46 0.40 0 0.6 40.0 14.0 14 7.90 0.42
Flåt07 3.75 1.10 1 14.0 689.0 29.7 23 16.90 0.84
Flåt08 1.77 0.60 0 9.1 436.0 14.7 13 11.00 0.58
------------------
Sample No. Cs* La* Ce* Li* Be* P* Sc* Te* Hf*
FLÅT 06-1
FLÅT 06-2
FLÅT 06-3
FLÅT 06-4 54.00
Flåt01 0.50 19.80 43.00 2 0 1740 7.60 4.77 0.10
Flåt02 1.32 54.60 122.50 6 1 3870 15.00 2.25 0.90
Flåt03 0.57 44.40 100.50 11 1 4400 22.60 1.42 0.80
Flåt04 1.04 36.60 79.40 2 0 3690 8.60 3.48 0.20
Flåt05 2.01 62.20 142.50 9 1 6970 22.70 0.88 0.70
Flåt06 0.15 41.80 90.20 0 1 3110 13.80 2.23 0.40
Flåt07 1.92 103.00 217.00 4 1 8930 15.20 0.61 0.60
Flåt08 1.06 49.70 102.50 3 1 4870 12.80 4.05 0.30
------------------
Sample No. Re* Tl*
FLÅT 06-1
FLÅT 06-2
FLÅT 06-3
FLÅT 06-4
Flåt01 36 0
Flåt02 13 0
Flåt03 7 1
Flåt04 21 0
Flåt05 6 1
Flåt06 22 0
Flåt07 9 0
Flåt08 17 0

The fact sheet was created on 20.10.2025
Questions or comments regarding the fact sheet can be emailed to:
ressursdatabaser@ngu.no
Copyright © 2025 Geological Survey of Norway