Norsk versjon
	THE ???? DATABASE
	Occurence 0 - 000 FEIL
	(Object Id: ) (Last updated: 18.03.2024)

Products

	Element/product	Crude ore grade or quality	Reg. date
	Cu	0.85 %	29.01.2001
	Zn	3.5 %	29.01.2001

Operations

	From - To	Activity	Comments
	1783 - 1787	Regular production	Company/Institution :Fredriks Gave Verk
	1842 - 1845	Regular production	Company/Institution :Røros Kobberverk
	1906 - 1940	Test mining	Company/Institution :The Foldal Copper and Sulphur ltd.
	1941 - 1952	Regular production	Company/Institution :Folldal Verk A/S
	1991 - 1994	Detail mapping	Company/Institution :T. Bjerkgård, University of Oslo
	1999 - 1999	Sampling	Company/Institution :NGU mineralressurser

Mineralization

	Era:	Paleozoic	Period:	Ordovician
	Genesis:	Volcex	Form:	Layer
	Main texture:	Banded	Min. distribution:	Massive (>50 % ore minerals)

Main grain size:

Medium grained (1-3 mm)

Main alteration:

Chloritisation

	Strike/Dip:	293 / 70	Direction:	270
			Plunge:	15

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	Chlorite	Subordinate mineral (1-10%)
	Gangue mineral	Sericite	Subordinate mineral (1-10%)
	Gangue mineral	Titanite	Accessory mineral (<1%)
	Gangue mineral	Clinozoisite	Accessory mineral (<1%)
	Gangue mineral	Biotite	Accessory mineral (<1%)
	Gangue mineral	Dolomite	Accessory mineral (<1%)
	Gangue mineral	Clinoamphibole	Accessory mineral (<1%)
	Gangue mineral	Ankerite	Accessory mineral (<1%)
	Ore mineral	Sphalerite	Major mineral (>10%)
	Ore mineral	Chalcopyrite	Major mineral (>10%)
	Ore mineral	Pyrite	Major mineral (>10%)
	Ore mineral	Pyrrhotite	Major mineral (>10%)
	Ore mineral	Galena	Subordinate mineral (1-10%)
	Ore mineral	Magnetite	Accessory mineral (<1%)
	Ore mineral	Altaite	Accessory mineral (<1%)
	Ore mineral	Hessite	Accessory mineral (<1%)
	Ore mineral	Pentlandite	Accessory mineral (<1%)
	Ore mineral	Molybdenite	Accessory mineral (<1%)
	Ore mineral	Arsenopyrite	Accessory mineral (<1%)
	Ore mineral	Bismuth	Accessory mineral (<1%)
	Ore mineral	Gold	Accessory mineral (<1%)

Lithology:

	Relationship	Rock	Origin
	Wall rock	Tuffite/chlorite schist	Sedimentary Original rock :Tuffite
			Metamorphic facies :Greenschist
	Wall rock	Quartz keratophyre	Extrusive Original rock :Rhyodacite
			Metamorphic facies :Greenschist

Information(s) in free text format

Free text

Nygruva mine was in production in three periods from 1783 to 1952. In total 0.3 Mt ore was produced with 0.85 % Cu and 3.5 % Zn. The ruler-shaped deposit has a length of 680 m, width of 60-70 m and an average thickness of 3 m. Two normal-faults cut across the deposit of which the westernmost one marks the end of the known deposit. Investigations (as late as in 1990) to find the continuation have not been successful. The massive part of the ore is a banded pyrite-sphalerite ore with lesser chalcopyrite and pyrrhotite in a quartz-calcite matrix. In the stratigraphic footwall of the massive ore are irregular lenses of zinc- or copper-rich ore, which locally are enriched in gold (up to 7.1 ppm).

Bibliography:

From NGU's Reference Archive:

Marlow, Wolmer , 1935

	Foldal. Beskrivelse til geologiske rektangelkart. D. Grubebeskrivelser. 1. Beskrivelse av Foldals kisfelt: 1. Foldals verks gruber. 2. Statens kisanvisninger. 3. Grimsboskjerpene. 4. Rødalens grube. 5. Tronfjellets grube. 6. Verkjensdalens kisfelt.

;Norges geologiske undersøkelse;KARTBESKRIVELSE; TIDSSKRIFTARTIKKEL;NGU; No.145;69-96 pages

Riiber, Carl C. , 1923

	Rapporter over kis -og kobbergruber og skjerp i Foldal, Dovre og Alvdal herreder.

;Norges geologiske undersøkelse;FAGRAPPORT;Bergarkivet; No.BA 3194;25 pages

Abstract:

Rapporten omfatter følgende gruver og skjerp: I. Foldals verks gruber: a. Hovedgruben. b. Nordre Gjeitryggen grube. c. Søndre jetryggen grube, d. Grev Moltke grube. e. Grimsdalen grube. f. Storthaab grube. g. Boksberg grube. II. Statens kisanvisninger: a. Skjerp øst for Foldals verks hovedgrube. b. Stretlien skjerp. c. Grimsdalen skjerp. III. Grimsbo kisskjerp. IV. Rødalens kobbergrube. V. Tronfjeldets kobbergruber. VI. Verkjendalens kisfelt. Rapporten beskriver forekomstenes beliggenhet, geologiske forhold, malmen, resultater av undersøkelser (boringer, analyser osv.), salgspriser, historiske forhold, juridiske forhold og kraftsituasjonen. Forekomstnr.: 1. 10963, 2. 10973 og 3. 10991. Forekomstens navn og koordinater: 1. Folldal 32 5521 68908, 2. Verkensdalen 32 5281 68816, 3. Gamle Tron 32 5862 68910.

Aasgaard, Gunnar , 1935

	Foldal. Beskrivelse til det geologiske rektangelkart. D. grubebeskrivelser. 1. Beskrivelse av Foldals kisfelt : geologisk oversikt

;Norges geologiske undersøkelse;KARTBESKRIVELSE; TIDSSKRIFTARTIKKEL;NGU; No.145;65-68 pages

Abstract:

In the territory covered by the map there are several mines and also useful rocks. The pyrites are of the greatest economical value. The most important among these are the Foldal mines. In the last three years 1932-1934 the yearly production has been about 40 000 to 50 000 tonn of pyrites containing 1.85-1.90% Cu and 45% S. Other pyrite mines not working at the present, however, are Røstvangen mines, Auma, Rødals- and St. Knuts mines and several smaller places. Of useful rocks there are soapstone occurrences in the Brekkebekkdal, at Strømsås, on the Strålsjøås, and on the Reinsliås. Limestone is found near the Randmelsøyr beside the Foldal road, at the north end of Savalen and in the neighbourhood of Røstvangen. The trondhjemite, which is a bright and pretty rock has been used as buildingstone. It is, however, not worked out at present in this district on account of the transport difficulties, but at Støren there is a quarry of it. There is also a slate quarry in the neighbourhood of Arleite beside the Foldal road.

Riiber, C.C.; Aasgaard, Gunnar , 1935

	Foldal. Beskrivelse til det geologiske rektangelkart. D. grubebeskrivelser. Beskrivelse av kis- og kobbergruber og skjerp i Foldal, Dovre og Alvdal herreder

;Norges geologiske undersøkelse;KARTBESKRIVELSE; TIDSSKRIFTARTIKKEL;NGU; No.145;68-69 pages

Bjerkgård, Terje , 1995

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

;UiO Geologisk fellesråd;AVHANDLING

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.

Sakshaug, G.F.; Brækken, H. , 1942

	Elektromagnetisk undersøkelse Moltke Grube Vest

;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.31;9 pages

Sakshaug, G. F.; Brækken, H. , 1940

	Elektromagnetisk undersøkelse Moltke Grube og Gjetryggen Søndre Grube.

;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.21;23 pages

Bugge, Arne , 1948

	Rapport fra befaring ved Folldal gruver.

;Norges geologiske undersøkelse;FAGRAPPORT;Bergarkivet; No.BA 784;5 pages

Abstract:

Befaringsrapport for gruvene Nordre og Søndre Gjeiteryggen og Grev Moltke Gruve. Det fremgår av ovenstående utredning at gruvene er drevet på kislinjaler og linser. De enkelte kislinjalene er i forhold til andre kislinjaler i Tronheimsdistriktet av relativt liten utstrekning; men ved vellykkete skjerpningsarbeider i dagen og i gruvene har man stadig funnet nye linser og linjaler når de gamle er utdrevet. Gruvedriften blir på denne måten kostbar, da de nye forekomster stadig drar seg bort fra de gamle sjakter.

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

Carstens, C.W. & Engzelius, J.G. 1946: Hvorledes den forkastede Moltkegang ble funnet. Tidsskr. for kjemi, bergvesen og metallurgi, 9, p.108-110.

Heim, J.G. 1972: Zur geologie des Südlichen Trondheim-gebietes. Unpubl. Ph.D. thesis, Univ. Mainz, 156 pp.

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.

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

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

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	BH11/2: 21.18-21.70	Core	Sampler: T. Bjerkgård Comment: Massive pyrite-sphalerite in chlorite-quartz, some calcite No. of registrated element analyses = 1
	BH11/2: 21.70-22.50	Core	Sampler: T. Bjerkgård Comment: Massive pyrite-sphalerite in chlorite-quartz, some calcite No. of registrated element analyses = 1
	BH13/2: 13.75-14.20	Core	Sampler: T. Bjerkgård Comment: Massive pyrite in quartz, some chalcopyrite and sphalerite No. of registrated element analyses = 1
	BH13/2: 9.50-9.60	Core	Sampler: T. Bjerkgård Comment: Massive pyrite with quartz matrix No. of registrated element analyses = 1
	BH16: 1.25-1.80	Core	Sampler: T. Bjerkgård Comment: Massive pyrite-sphalerite-pyrrhotite, matrix of quartz with some calcite No. of registrated element analyses = 1
	BH16: 1.80-2.55	Core	Sampler: T. Bjerkgård Comment: Massive pyrite-sphalerite-pyrrhotite, matrix of quartz with some calcite No. of registrated element analyses = 1
	BH16: 2.55-3.35	Core	Sampler: T. Bjerkgård Comment: Quartz-sericite schist with mainly iron sulfides No. of registrated element analyses = 1
	BH16: 3.35-3.42	Core	Sampler: T. Bjerkgård Comment: Massive pyrite-sphalerite, some chalcopyrite. Quartz-calcite matrix. No. of registrated element analyses = 1
	BH16: 3.55-3.64	Core	Sampler: T. Bjerkgård Comment: Massive pyrite-sphalerite, some chalcopyrite. Quartz-calcite matrix. No. of registrated element analyses = 1
	BH2/1: 11.35-11.60	Core	Sampler: T. Bjerkgård Comment: Quartz-sericite impregnation with pyrrhotite-sphalerite impregnation No. of registrated element analyses = 1
	BH2/1: 13.20-14.35	Core	Sampler: T. Bjerkgård Comment: rich impregnation of pyrite, sphalerite and pyrrhotite in quartz-calcite matrix No. of registrated element analyses = 1
	BH2/1: 20.80-21.05	Core	Sampler: T. Bjerkgård Comment: Quartz-sericite schist with sphalerite-chalcopyrite impregnation No. of registrated element analyses = 1
	BH2/1: 21.65-22.50	Core	Sampler: T. Bjerkgård Comment: Massive pyrrhotite-pyrite with lesser sphalerite and chalcopyrite. Quartz-calcite matrix No. of registrated element analyses = 1
	BH2/1: 48.60-49.00	Core	Sampler: T. Bjerkgård Comment: Rich pyrite-chalcopyrite-sphalerite impregnation in quartz-sericite-chlorite schist No. of registrated element analyses = 1
	BH2/1: 49.00-49.32	Core	Sampler: T. Bjerkgård Comment: Rich pyrite-chalcopyrite-sphalerite impregnation in quartz-sericite-chlorite schist No. of registrated element analyses = 1
	BH3/2: 14.30-15.00	Core	Sampler: T. Bjerkgård Comment: Semimassive chalcopyrite-pyrrhotite, some pyrite and sphalerite. Quartz-dominated matrix No. of registrated element analyses = 1
	BH3/2: 22.10-22.70	Core	Sampler: T. Bjerkgård Comment: Massive pyrite-sphalerite in quartz-calcite matrix No. of registrated element analyses = 1
	BH3/2: 27.65-28.30	Core	Sampler: T. Bjerkgård Comment: Rich pyrrhotite-chalcopyrite-sphalerite impr. in quartz-calcite with chlorite bands. No. of registrated element analyses = 1
	BH3/2: 33.75-34.30	Core	Sampler: T. Bjerkgård Comment: Rich impr. of pyrite, sphalerite, chalcopyrite and pyrrhotite in quartz-chlorite No. of registrated element analyses = 1
	BH3/2: 7.80-8.40	Core	Sampler: T. Bjerkgård Comment: massive sphalerite-pyrite. Quartz matrix. No. of registrated element analyses = 1
	BH5/3: 49.50-49.90	Core	Sampler: T. Bjerkgård Comment: very rich impr. of pyrite, sphalerite and chalcopyrite in quartz-calcite-chlorite matrix. No. of registrated element analyses = 1
	BH8/2: 15.80-16.10	Core	Sampler: T. Bjerkgård Comment: Massive chalcopyrite-sphalerite-pyrrhotite in quartz-calcite matrix No. of registrated element analyses = 1
	BH8/2: 23.35-23.75	Core	Sampler: T. Bjerkgård Comment: Massive pyrite-sphalerite. Quartz-calcite matrix. No. of registrated element analyses = 1
	BH8/2: 25.15-25.40	Core	Sampler: T. Bjerkgård Comment: Chlorite-quartz rock with rich pyrrhotite-chalcopyrite impregnation No. of registrated element analyses = 1
	BH8/2: 25.40-25.75	Core	Sampler: T. Bjerkgård Comment: Massive pyrite-sphalerite-chalcopyrite in quartz-calcite No. of registrated element analyses = 1
	BH9/2: 11.15-11.36	Core	Sampler: T. Bjerkgård Comment: Massive sphalerite with lesser pyrite and chalcopyrite. Quartz-calcite matrix. No. of registrated element analyses = 1
	BH9/2: 15.00-15.20	Core	Sampler: T. Bjerkgård Comment: massive pyrrhotite-sphalerite-chalcopyrite with quartz-calcite matrix No. of registrated element analyses = 1
	BH9/2: 15.20-15.50	Core	Sampler: T. Bjerkgård Comment: Pyrrhotite lenses with sphalerite and chalcopyrite in chlorite No. of registrated element analyses = 1
	BH9/2: 9.45-10.25	Core	Sampler: T. Bjerkgård Comment: Chloritic quartz-sericite schist. Pyrrhotite with som sphalerite and chalcopyrite in zones of impregnation No. of registrated element analyses = 1
	HE0058.01	Dump	Sampler: T. Bjerkgård/...Stored: Løkken/...Size(kg): 3 Comment: Chlorite-quartz schist containing 2-4 cm massive pyrite-sphalerite bands. No. of registrated element analyses = 1
	HE0058.02	Dump	Sampler: T. Bjerkgård/...Stored: Løkken/...Size(kg): 3 Comment: Massive homogeneous pyrite-sphalerite ore. mm-sized sulfide grains. No. of registrated element analyses = 1
	HE0058.03	Dump	Sampler: T. Bjerkgård/...Stored: Løkken/...Size(kg): 3 Comment: Massive pyrite-sphalerite ore, 1-1.5 mm sulfide grains. No. of registrated element analyses = 1
	HE0058.04	Dump	Sampler: T. Bjerkgård/...Stored: Løkken/...Size(kg): 3 Comment: Semimassive pyrrhotite-chalcopyrite-pyrite ore with subordinate sphalerite in quartz. No. of registrated element analyses = 1
	HE0058.05	Dump	Sampler: T. Bjerkgård/...Stored: Løkken/...Size(kg): 3 Comment: Semimassive to rich impregnation of pyrite in chloritic sericite schist. No. of registrated element analyses = 1
	HE0058.06	Dump	Sampler: T. Bjerkgård/...Stored: Løkken/...Size(kg): 3 Comment: Quartz-chlorite schist with scattered 2-3 mm pyrite cubes. No. of registrated element analyses = 1
	HE0058.07	Dump	Sampler: T. Bjerkgård/...Stored: Løkken/...Size(kg): 3 Comment: Semimassive pyrite-chalcopyrite mineralization in matrix of quartz and carbonate. No. of registrated element analyses = 1

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

Name of Locality: Nygruvtjønna skjerp

(Object Id: 12387 6,01,00)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

Coordinate system:

UTM-Zone 33 - EUREF89/WGS84

East:

548200 m.

North:

6887300 m.

Longitude:

9.9236510

Latitude:

62.1132000

Show on map

Resource

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

Resources and production

	Activity:	Pitting	Reserves:
	Operating method:		Historical production:

Operations

	From - To	Activity	Comments
		Pitting	Company/Institution :Folldal verk A/S
	1991 - 1994	Detail mapping	Company/Institution :T. Bjerkgård, University of Oslo
	1999 - 1999	Sampling	Company/Institution :NGU mineralressurser

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Quartz	Major mineral (>10%)
	Gangue mineral	Amphibole	Subordinate mineral (1-10%)
	Ore mineral	Pyrrhotite	Major mineral (>10%)
	Ore mineral	Chalcopyrite	Subordinate mineral (1-10%)

Lithology:

	Relationship	Rock	Origin
	Wall rock	Chlorite schist	Sedimentary Original rock :Tuffite
			Metamorphic facies :Greenschist
	Wall rock	Quartz keratophyre	Extrusive Original rock :Rhyodacite
			Metamorphic facies :Greenschist

Information(s) in free text format

Free text

Skjerpet ligger like øst for Nygruvtjønna og består av en grøft ca. 30 m lang på tvers av strøket til bergartene, dvs. i NNV retning. 10 meter av grøfta i nord er inntil 3 meter dyp og 4 m bred mens resten av grøfta mot sør er gjengrodd og antakelig kun røsket ned på fast fjell. Mineralisering består vesentlig av meget finkornet magnetkis med underordnet kobberkis i sterkt silisifisert skifer (prøve HE0058.08). Stedvis opptrer opptil 1-2 cm lange uorienterte nåler av amfibol (prøve HE0058.09).

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	HE0058.08	Dump	Sampler: T. Bjerkgård/...Stored: Løkken/...Size(kg): 3 Comment: Weak impregnation of finegrained pyrrhotite and minor chalcopyrite in strongly silicified schist No. of registrated element analyses = 1
	HE0058.09	Dump	Sampler: T. Bjerkgård/...Stored: Løkken/...Size(kg): 3 Comment: Weak, finegrained pyrrhotite impregnation in strongly silicified schist with needles of amphibole. Minor chalcopyrite. No. of registrated element analyses = 1

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

Name of Locality: Nygruvhøgda skjerp

(Object Id: 12388 6,02,00)

Location

County:

Municipality:

Mangler ()

Map 1:50000:

Folldal (1519-2)

Map 1:250000:

Røros

Coordinate system:

UTM-Zone 33 - EUREF89/WGS84

East:

546970 m.

North:

6886580 m.

Longitude:

9.8998930

Latitude:

62.1068930

Show on map

Resource

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

Resources and production

	Activity:	Pitting	Reserves:
	Operating method:		Historical production:

Operations

	From - To	Activity	Comments
		Pitting	Company/Institution :Folldal Verk A/S
	1991 - 1994	Detail mapping	Company/Institution :T. Bjerkgård, University of Oslo

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Chlorite	Major mineral (>10%)

Lithology:

	Relationship	Rock	Origin
	Wall rock	Chlorite schist	Sedimentary Original rock :Tuffite
			Metamorphic facies :Greenschist

Information(s) in free text format

Free text

Skjerpet består av en 12 m lang og inntil 0.75 m dyp røskegrøft, dels gjengrodd. Grøfta er drevet på tvers av strøket, dvs. i VNV-ØNØ retning. Det er ikke funnet synlige sulfider her og bergarten i skjerpet er en noe rusten klorittskifer, sannsynligvis en noe omvandlet mafisk tuffitt. Skjerpet ligger i sørskråningen av Nygruvhøgda, ned mot Streitmyrene.

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The fact sheet was created on 02.05.2024

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