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	THE ???? DATABASE
	Deposit 0 - 000 FEIL
	(Object Id: ) (Last updated: 18.03.2024)

Products

	Element/product	Crude ore grade or quality	Reg. date
	Cu	0,51 %	09.02.2001
	S	29,6 %	14.12.2001
	Zn	2,34 %	09.02.2001

Operations

	From - To	Activity	Comments
	1783 - 1788	Regular production	Company/Institution :Fredriks Gaves verk
	1920 - 1920	Test mining	Company/Institution :The Folldal Copper and Sulphur ltd.
	1949 - 1949	Geophysics	Company/Institution :Geofysisk Malmleting
	1950 - 1951	Geophysics	Company/Institution :Geofysisk Malmleting
	1966 - 1966	Geology	Company/Institution :Folldal Verk A/S
	1966 - 1966	Geophysics
	1969 - 1969	Core drilling	Company/Institution :Folldal Verk A/S
	1969 - 1969	Geophysics	Company/Institution :Geofysisk Malmleting
	1977 - 1979	Geology	Company/Institution :S.A.S. Pedersen, Univ. of Copenhagen
	1989 - 1990	Core drilling	Company/Institution :Folldal Verk A/S

Mineralization

	Era:	Paleozoic	Period:	Ordovician
	Dating:	488 (-2\+2) million year	Method:	U/Pb
	Genesis:	Volcex	Form:	Plate
	Main texture:	Banded	Min. distribution:	Massive (>50 % ore minerals)

Main grain size:

Medium grained (1-3 mm)

Main alteration:

Sericitisation

	Strike/Dip:	240 / 60	Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Paleozoic

Period:

Ordovician

	Province:	Caledonides
	Geotec.unit:	Trondheim Nappe Complex
	Tectonic complex:	Meråker Nappe
	Igneous complex:

Group:

Fundsjø

Formation:

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Calcite	Major mineral (>10%)
	Gangue mineral	Quartz	Major mineral (>10%)
	Gangue mineral	Muscovite	Subordinate mineral (1-10%)
	Gangue mineral	Chlorite	Subordinate mineral (1-10%)
	Gangue mineral	Plagioclase	Accessory mineral (<1%)
	Gangue mineral	Epidote	Accessory mineral (<1%)
	Gangue mineral	Clinoamphibole	Accessory mineral (<1%)
	Gangue mineral	Biotite	Accessory mineral (<1%)
	Ore mineral	Pyrite	Major mineral (>10%)
	Ore mineral	Pyrrhotite	Major mineral (>10%)
	Ore mineral	Magnetite	Subordinate mineral (1-10%)
	Ore mineral	Sphalerite	Subordinate mineral (1-10%)
	Ore mineral	Chalcopyrite	Subordinate mineral (1-10%)
	Ore mineral	Hessite	Accessory mineral (<1%)
	Ore mineral	Molybdenite	Accessory mineral (<1%)
	Ore mineral	Galena	Accessory mineral (<1%)
	Ore mineral	Tellurobismuthite	Accessory mineral (<1%)

Lithology:

	Relationship	Rock	Origin
	Wall rock	Quartz keratophyre	Extrusive Original rock :Rhyodacite
			Metamorphic facies :Greenschist
	Wall rock	Trondhjemite	Intrusive Original rock :Trondhjemite
			488 (-2\+2) mill. years;..Method:U/Pb
			Metamorphic facies :Greenschist
	Wall rock	Banded quartz-albite schist	Sedimentary Original rock :Tuffite
			Metamorphic facies :Greenschist
	Wall rock	Banded chlorite schist	Sedimentary Original rock :Tuffite
			Metamorphic facies :Greenschist

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Wall rock	Foliation	Strike/Dip :240 / 61	Post-mineralisation ;...Effect :Modifies
	Wall rock	Fold axis	Dir./Plunge :257 / 34	Post-mineralisation ;...Effect :Modifies
	Wall rock	Mineral lineation	Dir./Plunge :263 / 44	Post-mineralisation ;...Effect :Modifies

Information(s) in free text format

Free text

The Grimsdalen deposit is by far the largest in the Folldal ore district, comprising an identified resource of 8.29 mill.t. of ore with 0.5 % Cu and 2.3 % Zn. The probable resource is calculated to 14.3 mill.t. and possible resource close to 18.5 mill.t., according to data from Folldal Verk AS. However, the thickness of the mineralized layer was found to be to small to be economic, at the time the evaluation was done (1991). The overall length of the deposit is 9 km, the maximum widt 1000 m and average thickness 3 m. A major fault divides the deposit in an eastern and a western body. Folding has led to local thickening of the ore zone. The deposit is hosted by banded tuffitic (amphibole-chlorite) schists with intercalations of graphite schist. The mineralization is dominated by pyrite, while pyrrhotite, chalcopyrite and sphalerite occur in varying but generally subordinate amounts. Gangue is mainly quartz and calcite.

Bibliography:

From NGU's Reference Archive:

Bjerkgård, Terje , 1995

	The stratabound massive sulfide deposits in the Folldal area, southern Trondheim region Caledonides, Norway.

;UiO Geologisk fellesråd;AVHANDLING

Pedersen, Stig Asbjørn Schack , 1979

	Structures and ore genesis of the Grimsdalen deposits, southern Trondheim region, Norway.

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.351;77-98 pages

Abstract:

The central part of the Grimsdalen area of the southern Trondheim region is occupied by a sequence of metavolcanics with subordinate metasediments, termed the Folla Group, which are correlated with the Støren Group of the central and western parts of the region. The Folla Group is thrust above arkosic sparagmites and is itself overthrust by metasediments of the Mesæterhø Group. A tectonic model for the Grimsdalen area, which has been affected by two major phases of deformation, is presented. The sulphide deposits of the area occur in a single pyritite horizon within the Follo Group, and 4 ore types have been differentiated. The metamorphic evolution of the pyritite and the different generations of pyrite are discussed in relation to the structural and metamorphic history of the Folla Group sequence.

Bjerkgård, Terje; Bjørlykke, Arne , 1994

	The stratabound sulphide deposits in the Folldal area, Southern Trondheim Region, Norway

;Norsk geologisk forening;TIDSSKRIFTARTIKKEL;Norsk geologisk tidsskrift; No.74 (4);213-237 pages

Abstract:

Frie emneord: Lagdelt, Malmgenese Five strata-bound massive sulphide deposits are situated at three different stratigraphic levels in the volcanogenic Fundsjø group in the Folldal area. The deposits are hosted in metabasalts, metarhyodacites and volcanoclastic rocks and belong to the Cu-Zn class of volcanic-associated massive sulphide deposits. The metal content of the deposits indicates that the sources of metals are underlying strata, possibly with a contribution from intrusives. Wall rock alteration varies according to differences in host rocks, and is probably a result of chemical variations of the host rocks, temperature differences and proximity to the hydrothermal vent. The clustering of deposits in the Folldal area is considered to be due to the occurrence of a large sub- volcanic trondhjemitic intrusion which acted as the major heat engine for convection. The small size of the deposits might be related to the shallow level of the intrusion.

Sturt, Brian A.; Bøe, Reidulv; Ramsay, Donald M.; Bjerkgård, Terje , 1995

	Stratigraphy of the Otta-Vågå tract and regional stratigraphic implications

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU Bulletin; No.427;25-28 pages

Singsaas, P. , 1959

	Geofysisk undersøkelse 1. Grimsdal Grube - Husumskogen 2. Verket - Knutshovdet 3. Søndre Gjetryggen Grube - Grimsbu.

;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.173;10 pages

Singsaas, P.; Brækken, H. , 1950

	Geofysisk undersøkelse Grimsdal Grube, Hovedgruben.

;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.69;31 pages

Singsaas, Per , 1971

	El.magn. bakkemålinger Verkenseter i Grimsdalen.

;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.972 A;6 pages

Singsaas, Per , 1970

	El.magn. borhullsmålinger Grimsdalen Grube.

;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.901 B;4 pages

References not to be found in NGU's Reference Archive.:

Bjerkgård, T. & Bjørlykke A.,1996: Sulfide deposits in Folldal, Southern Trondheim Region Caledonides, Norway: Source of metals and wall-rock alterations related to host rocks. Economic Geology vol.91, p.676-696.

Bjerkgård, T. & Bjørlykke, A. 1995: Geology of the Folldal area, southern Trondheim Region Caledonides, Norway. NGU bull. 426, p.53-75.

Per B. Støen 1948: Folldal Verk gjennom 200 år. Historiske trekk: 1748-1948. festskrift Folldal Verk A/S, 70 sider.

Name of Sample point: Bh 95 Grimsdalsgruva

(Object Id: 39296 5,00,01)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Copper
			Element(s):	Kis Zn Cu

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	BH 95: 294.5-294.8	Core	Sampler: T. Bjerkgård Comment: Magnetkis-pyrittmalm med underordnet kobberkis og sinkblende. 20-30 cm soner anriket på mørk grønn kloritt med spredte cm-lange amfibolnåler. No. of registrated element analyses = 1
	BH 95: 294.8-295.6	Core	Sampler: T. Bjerkgård Comment: Magnetkis-pyrittmalm med underordnet kobberkis og sinkblende. 20-30 cm soner anriket på mørk grønn kloritt med spredte cm-lange amfibolnåler. No. of registrated element analyses = 1
	BH 95:295.6-296.1	Core	Sampler: T. Bjerkgård Comment: Magnetkis-pyrittmalm med underordnet kobberkis og sinkblende. 20-30 cm soner anriket på mørk grønn kloritt med spredte cm-lange amfibolnåler. No. of registrated element analyses = 1
	BH 95:296.1-297.1	Core	Sampler: T. Bjerkgård Comment: Magnetkis-pyrittmalm med underordnet kobberkis og sinkblende. 20-30 cm soner anriket på mørk grønn kloritt med spredte cm-lange amfibolnåler. No. of registrated element analyses = 1
	DBH 95:297.1-297.4	Core	Sampler: T. Bjerkgård Comment: Magnetkis-pyrittmalm med underordnet kobberkis og sinkblende. 20-30 cm soner anriket på mørk grønn kloritt med spredte cm-lange amfibolnåler. No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Bh 6 Grimsdalsgruva

(Object Id: 39297 5,00,02)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Copper
			Element(s):	Kis Zn Cu

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	BH 6 (87.06-89.65)	Core	Sampler: T. Bjerkgård Comment: Massiv pyritt-sinkblende-kobberkis-magnetkismalm. Pyritt opptrer som 1-8 mm porfyroblaster. Malmsonen er skarpt avgrenset. No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Bh 21 Grimsdalsgruva

(Object Id: 39298 5,00,03)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Copper
			Element(s):	Kis Zn Cu

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	BH 21 (93.40-94.70)	Core	Sampler: T. Bjerkgård Comment: Massiv pyritt-sinkblendemalm med noe kobberkis. Innslag av magnetkis i nedre deler av intervallet. Matriks av kvarts og kalkspat. No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Bh 7 Grimsdalsgruva

(Object Id: 39299 5,00,04)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Copper
			Element(s):	Kis Zn Cu

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	BH 7 (108.00-109.90)	Core	Sampler: T. Bjerkgård No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Bh 29 Grimsdalsgruva

(Object Id: 39300 5,00,05)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Copper
			Element(s):	Kis Zn Cu

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	BH 29 (39.03-41.28)	Core	Sampler: T. Bjerkgård Comment: Massiv pyritt-magnetkismalm med noe kobberkis og sinkblende. Ikke-sulfider er kloritt, kalkspat og kvarts. No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Bh 19 Grimsdalsgruva

(Object Id: 39301 5,00,06)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Copper
			Element(s):	Kis Zn Cu

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	BH 19 (15.27-16.87)	Core	Sampler: T. Bjerkgård No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

Name of Locality: adit 1 b

(Object Id: 32669 5,01,00)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Zinc
			Element(s):	Kis Zn Cu

Name of Sample point: Bh 90-07

(Object Id: 39196 5,01,01)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Copper
			Element(s):	Kis Zn Cu

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	Bh90-07, 75.15-75.70	Core	Sampler: T. Bjerkgård/J.S. Sandstad No. of registrated element analyses = 1
	Bh90-07, 75.85-76.35	Core	Sampler: T. Bjerkgård/J.S. Sandstad No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

Name of Locality: adit I

(Object Id: 32671 5,02,00)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Zinc
			Element(s):	Kis Zn Cu

Name of Locality: adit no.1

(Object Id: 32674 5,03,00)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Zinc
			Element(s):	Kis Zn Cu

Name of Locality: adit no.2

(Object Id: 32675 5,04,00)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Zinc
			Element(s):	Kis Zn Cu

Name of Locality: adit no.3

(Object Id: 32676 5,05,00)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Zinc
			Element(s):	Kis Zn Cu

Name of Locality: Showing

(Object Id: 32680 5,06,00)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Hjerkinn (1519-3)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Zinc
			Element(s):	Kis Zn Cu

Name of Sample point: Bh 89-05

(Object Id: 39197 5,06,01)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Hjerkinn (1519-3)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Copper
			Element(s):	Kis Zn Cu

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	Bh89-05, 235.7-236.1	Core	Sampler: T. Bjerkgård/J.S. Sandstad No. of registrated element analyses = 1
	Bh89-05, 239.2-240.0	Core	Sampler: T. Bjerkgård/J.S. Sandstad No. of registrated element analyses = 1
	Bh89-05, 240.7-241.5	Core	Sampler: T. Bjerkgård/J.S. Sandstad No. of registrated element analyses = 1
	Bh89-05, 245.7-246.6	Core	Sampler: T. Bjerkgård/J.S. Sandstad No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Bh 89-09

(Object Id: 39198 5,06,02)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

County:

UTM-Zone 33 - EUREF89/WGS84

Resource

	Resource Type:	Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn)	Resource Subtype:	Copper
			Element(s):	Kis Zn Cu

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	Bh89-09, 59.0-60.0	Core	Sampler: T. Bjerkgård/J.S. Sandstad No. of registrated element analyses = 1

NB! All analyse values are shown at the end of the printout.:

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The fact sheet was created on 06.05.2024

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