English version
	MALMDATABASEN
	Forekomstområde 137 - 002
	(Sist oppdatert 22.okt.2025)

Betydning

Offentlig:

Little Importance (reg. 18.02.2015)

Economical:

Lite viktig , (Confirmed 16.feb.2005 by Havard Gautneb)

Products

	Element/product	Crude ore grade or quality
	NI	1.5 %

Mineralization

	Era:	Proterozoic	Period:	Mesoproterozoic
	Dating:		Method:
	Genesis:	Ortomagmatisk	Form:
	Main texture:		Min. distribution:

Main grain size:

Main alteration:

	Strike/Dip:		Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Proterozoic

Period:

Mesoproterozoic

	Province:	East Norwegian Basement Province
	Geotec.unit:	Østfold Complex
	Tectonic complex:
	Igneous complex:

Group:

Formation:

Opplysning(er) i fritekstformat

Fri tekst

Forekomsten ligger i den trange Gjerdalen ca. 130 m nord for veien på vestsida av Flesjøvannet. En kort, vannfylt stoll med en dyp synk er drevet inn i vestveggen i dalen. Middelskornet, granittisk biotittgneis dominerer i veggene. Men nederst ved den sørlige inngangen til stollen er en minst 50 cm mektig sulfidsone synlig. Den består av disseminert magnetkis og kobberkis i biotittførende amfibolitt/metagabbro med anrikning av kobberkis i årer langs kontakten mot gneisen. Tippen er gjengrodd og består i hovedsak av gneis.

Bilde(r) fra forekomstområdet:

Photo no. 1 showing Flesjø skjerp" Photo no. 2 showing Massiv malm"

Bibliography:

From NGU's Reference Archive:

Rekstad, J. , 1921

	Eidsberg. De geologiske forhold innen rektangelkartet Eidsbergs område

;Norges geologiske undersøkelse;KARTBESKRIVELSE; BOK;NGU; No.88;76 pages

Abstract:

The territory is situated in south-eastern Norway to the east of the Oslofjord. It is an inland district which at no place reaches the sea. Glomma is the chief river which runs through the country in a southerly direction. The rocks occurring here are gneiss, granite, gabbro and schistose amphibolite, all of them of Archean age. Gneiss occupies a large area of the region. The rock has a varied appearance. Partly it is rich in mica (mica gneiss), partly it contains hornblende (hornblende-gneiss), partly it is coarse-grained and of granitoid texture. This latter form embraces also granite which has been deformed by powerful mechanical forces. This granite is intermixed with the gneiss in such a way as to make it impossible to separate them on the map. For the most part there is no distinctive demarcation between them, but the one passes into the other. The gneiss is mostly stratified, with well defined strike and dip. The granite intermixed is younger than the gneiss, but it belongs to the oldest known granites of Scandinavia. The gneiss is for the most part of igneous origin. Gabbro and amphibolite occur as numerous lenses injected into the gneiss. Connected with the gabbro here occurs nickelferous pyrrhotite. The greatest of these occurrences is at Romsås.

, 1940

	Aktenvermerk uber Nickelerz-Vorkommen in Smålenene.

;Norges geologiske undersøkelse;FAGRAPPORT;Bergarkivet; No.BA 1585;2 pages

	Abstract:
	Notatet gir opplysninger om nikkel-magnetkisforekomster i Smålenene, Spydeberg, Hobøl, Skiptvedt, Svendal, Rakkestad, Eidsberg, Trøgstad og Askim.

Foslie, Steinar , 1925

	Syd-Norges gruber og malmforekomster.

;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.126;1-89 + ka pages

Abstract:

On the map accompanying this paper all the mines and ore deposits of Southern Norway are collected for the first time.The material has been gathered from printed and unprinted sources, communications from mining engineers and geologists, and through personal visits. Included are all mines and ore deposits of former, present and future importance. Among the 1407 deposits on the map, there are furthermore included all of doubtful value and many which are quite unworkable, but of geological interest, or those which mark the distribution of ore bearing formations. For this reason it has been necessary to mark the deposits with signs of different size. The object is only to facilitate a comprehensive view of the map, and is not an effort of economic classification, which for most of them would be quite impossible. The sizes refer to the presumed importance of the ore deposit, and has nothing to do with the extent of the mining operations. Mines and deposits out of work during the period 1913-1923 have been separately marked (see the legend), also deposits which were formerly of much greater importance than now. For the smallest mines and deposits no distinction has been made in these respects. Among them are represented partly those, which are in reality unworkable, partly those which are little investigated.

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	Flesjø01	Bedrock	Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2 Kommentar :Kobberkis-rik åre langs kontakten til sidebergart/gneis No. of registrated element analyses = 1
	Flesjø02	Bedrock	Sampler :Mansur/Sandstad/...Stored :Løkken/...Size(kg) :2 Kommentar :Magnetkis+kobberkis disseminasjoni fin-/middelskornet biotitt-rik amfibolitt No. of registrated element analyses = 1

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

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Analyse Results

from

Forekomstområde 137 - 002 Flesjø

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#
Flesjø01	Bedrock	57900	417	3	358	9580	11.6	107.0
Flesjø02	Bedrock	9830	150	3	510	14350	1.8	27.0

------------------

Sample No.	Pt#	Pd#	As*	Cd*	Ba*	Mo*	Sn*	Sb*	Bi*
Flesjø01	25.0	925.0	3	3.1	160	2.74	4	0	5
Flesjø02	27.0	218.0	4	.8	190	2.28	4	0	4

------------------

Sample No.	Se*	Ga*	Ge*	In*	V*	Cr*	Mn*	Fe%	Th*
Flesjø01	36.00	11.90	0.44	0.39	108	780	563	18.25	1.04
Flesjø02	33.00	11.05	0.44	0.29	96	764	655	18.70	3.49

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Sample No.	U*	W*	Rb*	Sr*	Y*	Zr*	Nb*	Ta*	Cs*
Flesjø01	0.50	0	117.0	32.5	18.8	25	5.00	0.28	29.60
Flesjø02	0.60	0	156.5	64.1	15.7	28	3.40	0.22	23.40

------------------

Sample No.	La*	Ce*	Li*	Be*	P*	Sc*	Te*	Hf*	Re*
Flesjø01	6.90	17.70	82	4	320	25.50	4.09	0.90	81
Flesjø02	6.60	16.15	78	4	280	21.50	2.55	1.00	78

------------------

Sample No.	Tl*
Flesjø01	1
Flesjø02	1

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Faktaarket ble generert 10.06.2026

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