Norsk versjon
	THE ORE DATABASE
	Deposit Area 1833 - 070
	(Last updated 05.sep.2018)

Importance

Public:

Not Assessed (reg. 09.02.2017)

Economical:

Could be significant , (Confirmed 15.okt.2013 by Janja Knezevic)

Products

	Element/product	Crude ore grade or quality
	AG	20 ppm
	CU	.8 %
	KIS	60 %
	PB	.1 %
	ZN	3.5 %

Operations

	From - To	Activity	Comments
	1910 - 1911	Test mining
	1965 - 1965	Geology
	1968 - 1968	Geology
	1976 - 1976	Geophysics
	1980 - 1981	Geology
	1981 - 1982	Core drilling
	1984 - 1984	Geophysics
	2008 - 2009	Geology	Company/Institution :NGU

Mineralization

	Era:	Proterozoic	Period:	Neoproterozoic
	Dating:		Method:
	Genesis:	Volcex	Form:	Lens
	Main texture:	Porphyroblastic	Min. distribution:	Massive (>50 % ore minerals)

Main grain size:

Coarse grained (> 3 mm)

Main alteration:

	Strike/Dip:	255 / 70	Direction:	270
			Plunge:	20

Stratigraphic classification of host rock

Era:

Proterozoic

Period:

Neoproterozoic

	Province:	Caledonides
	Geotec.unit:	Rødingsfjell Nappe Complex
	Tectonic complex:	Uppermost Allochthon
	Igneous complex:

Group:

Mofjell Group

Formation:

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Muscovite	Major mineral (>10%)
	Gangue mineral	Plagioclase	Major mineral (>10%)
	Gangue mineral	Potassic feldspar	Major mineral (>10%)
	Gangue mineral	Quartz	Major mineral (>10%)
	Ore mineral	Pyrite	Major mineral (>10%)
	Ore mineral	Chalcopyrite	Subordinate mineral (1-10%)
	Ore mineral	Sphalerite	Subordinate mineral (1-10%)
	Ore mineral	Pyrrhotite	Subordinate mineral (1-10%)
	Ore mineral	Hematite	Accessory mineral (<1%)
	Ore mineral	Ilmenite	Accessory mineral (<1%)
	Ore mineral	Fahlore	Accessory mineral (<1%)
	Ore mineral	Marcasite	Accessory mineral (<1%)
	Ore mineral	Magnetite	Accessory mineral (<1%)
	Ore mineral	Galena	Accessory mineral (<1%)
	Ore mineral	Rutile	Accessory mineral (<1%)
	Ore mineral	Arsenopyrite	Accessory mineral (<1%)
	Ore mineral	Molybdenite	Accessory mineral (<1%)

Lithology:

	Relationship	Rock	Origin
	Host rock	Muskovittgneis	Extrusive Original rock :Tuff
			Metamorphic facies :Amphibolite
	Wall rock	Amfibolitt	Extrusive Original rock :Basalt
			Metamorphic facies :Amphibolite
	Wall rock	Granatglimmergneis	Sedimentary Original rock :Greywacke
			Metamorphic facies :Amphibolite

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Foliation	Strike/Dip :255 / 70	Post-mineralisation ;...Effect :None
	Host rock	Mineral lineation	Strike/Dip :270 / 20	Post-mineralisation ;...Effect :Modifies
	Host rock	Fold axis	Strike/Dip :270 / 20	Post-mineralisation ;...Effect :Modifies

Information(s) in free text format

Free text

The Heramb and Bertelberget deposits are the easternmost in the Raudvatnet zone of pyritiferous mica schist. They are c. 2 km apart, but may somehow be connected according to the regional geophysical data, including TURAM (Dalsegg, 84) and the 2007 TEM data by GEXCO. The geology in the area is characterized by several alternating thin layers of amphibolite, biotite gneiss and muscovite gneiss, separated by thicker units of grey gneiss. The latter is often quite homogeneous and massive (e.g. close to and to the west of Heramb, and is probably mainly of volcanic/intrusive origin (rhyolite/rhyodacite). The Bertelberget mineralization is different from Heramb, by having lenses and layers of coarse massive pyrite with pyrrhotite and lesser sphalerite and chalcopyrite. Average of 7 dump samples yielded 2.0 % Cu, 1.7 % Zn, 0.1 % Pb, 21 g/t Ag, 0.37 g/t Au. Test mining was carried out at Bertelberget in 1910 and 1911, at the same time as at Heramb. The workings included a 25 m long adit and some smaller pits. Both the adit and the main pit intersected quite rich copper and zinc ore over a thickness of 5-6 meters. Analyses from the adit carried out in 1952 and referred to by Kleinevoss (1967) yielded 0.7-1.17 % Cu, 2.82-3.81 % Zn and 46.4-47.6 % S. Six holes were drilled in 1982 and two intersected mineralization of 2.7-5.6 m thickness with 1.0-1.6 % Zn, 0.1-0.7 % Cu, 0.1 % Pb and 7-23 g/t Ag. In the deepest intersection was an interval of 1.25 m with 4.0 % Zn, 0.2 % Cu, 0.2 % Pb and 15 g/t Ag. The rather restricted drilling has not delimited the ore zone, which may extend more to the south than the depth of the deepest holes. However, the ore zone may be rather limited in length (2-300 m) according to the geophysical data.

Bibliography:

From NGU's Reference Archive:

Bjerkgård, Terje ; Marker, Mogens ; Slagstad, Trond ; Solli, Arne , 2008

	Mofjell-prosjektet. Statusrapport 2008

;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2008.088;25 s. pages

Abstract:

Rapporten gir en status for Mofjellprosjektet, et 4-årig samarbeidsprosjekt mellom GEXCO Norge AS og NGU. Prosjektområdet er øst og sør for Mo i Rana, et område som kan inneholde økonomiske sulfidforekomster med Cu, Zn, Pb, Ag og Au. Målet er å få fram dette potensialet gjennom å kartlegge berggrunnen, de kjente og delvis drevne sulfidforekomstene og andre mineraliseringer i området. Berggrunnskartleggingen i 2008 har fokusert på den østlige delen av området, som omfatter fortsettelsen av Plurdalgruppen sørover og relasjonen til bergartsgrupper i øst. Dette innbefatter den viktige tidlig Kaledonske skyvestrukturen som kalles Langfjellsonen, som kan representere et malmgeologisk provinsielt skille, med jernmalmene i nord og sulfidforekomstene i sør. Under feltarbeidet ble det systematisk innsamlet 95 bergartsprøver til geokjemi, geokronologi og petrologi for å undersøke bergartenes dannelse som bakgrunn for relasjonen til malmgenese. Malmgeologiarbeidet har i 2008 fokusert på å skaffe oversikt over sulfidforekomster i Mofjellgruppen og en rekke nøkkelforekomster i de forskjellige mineraliserte sonene er kartlagt og prøvetatt. I tillegg har GEXCO innsamlet mange prøver, dels i form av håndstykkeprøver og dels i form av boring med packsack utstyr. Sammen med resultater fra GEXCOs diamantboringer viser arbeidet så langt at en rekke forekomster og soner i området kan være av økonomisk interesse og bør følges opp videre. De mest interessante områdene og forekomstene i Mofjellgruppen som peker seg ut så langt i tillegg til forekomstene i Mofjellet og Sølvberget er Hellerfjellet, Hesjelia-Hammertjønna, Heramb-Bertelberget og Småvatnan. Mer arbeid med dataene, blant annet sammenholdt med data fra tidligere prospekteringsaktivitet i området, er nødvendig for å komme nærmere inn på potensialet i både de ovenfor nevnte forekomstene og andre i området.

Bjerkgård, Terje ; Slagstad, Trond ; Solli, Arne ; Marker, Mogens , 2009

	Mofjell-prosjektet: Statusrapport pr. juni 2009

;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2009.038;31 s. pages

Abstract:

I alt ble 95 bergartsprøver innsamlet under feltarbeidet i 2008; av disse 81 prøver for geokjemi og 26 prøver for mineralseparasjon og aldersbestesmmelse (de fleste av disse også for geokjemi). Geokjemi av både amfibolitter og felsiske metavulkanitter i Mofjellgruppen viser øybuesignatur. Resultatene er således i stor grad i overensstemmelse med det som tidligere er publisert. En god del av de grå gneisene ser ut til å representere felsiske metavulkanitter, noe som betyr at det er et større innslag av vulkanske bergarter i området enn tidligere antatt. Dette kan også være en av grunnene til at området er anomalt når det gjelder gull-innhold. Det blir viktig å identifisere de tykkere enhetene med grå gneis. Dersom disse er vulkanske, kan de ha vært viktige som både varme- og metallkilde for dannelse av sulfidforekomstene.

Bjerkgård, Terje; Marker, Mogens; Slagstad, Trond; Solli, Arne , 2013

	The Mofjell project: summary and conclusions

;Norges geologiske undersøkelse;RAPPORT;NGU-rapport; No.2013.048;87 pages

Abstract:

The Mofjell project commenced in 2008 as a cooperation between GEXCO Norge AS, the county administration of Nordland and NGU. As GEXCO faced financial difficulties the external funding ended in 2009. The project area included Mofjellet and the eastern part of Plurdalen, an area with a large potential for economic sulfide deposits with Zn, Cu, Pb, Ag and Au. NGU has focused on establishing the geological setting of the Mofjell Group and its relation to ore formation. Another very important goal has been to assess the potential for economic ore deposits in the area, including enrichment of precious metals. On the basis of lithological observations and geochemistry, the Mofjell Group consists of a largely bimodal volcanic-sedimentary assemblage formed in an island-arc to back-arc setting. The data also show that the proportion of felsic volcanic rocks is much higher than previously described. A bimodal volcanic suite mixed with sediments is a geological environment which is regarded as favorable for both rich and large sulfide deposits.

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

Spross, E. 1956: Bericht über die Untersuchungsarbeiten im Sommer 1956. Upubl. rapp.

Kruse, A. 1964: Oversikt over malmfelt og malmletingsarbeider i Ranen. Rapport Bergverksselskapet Nord-Norge.

Kleinevoss, A. 1967: Geologische Kartierung und petrographisch-lagerstättenkundliche Untersuchungen im Vester Mofjell/Rana - Distrikt, Nord-Norwegen. Diplomoppgave, Klausthal.

Kleine-Hering, R. 1968: Bericht über den Geologischen Untersuchungen im Bertekberg-Herambgruben - Gebiet (Vester Mofjell). Intern rapport. Bergverksselskapet Nord-Norge.

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	BB-01	Dump	Sampler :T. Bjerkgård Comment :Massive po-py-sl wit accessory cpy. coarse pyrite blasts No. of registrated element analyses = 1
	BB-02	Dump	Comment :Coarse pyrite with some chalcopyrite in chlorite-biotite rich matrix No. of registrated element analyses = 1
	BB-03	Dump	Sampler :T. Bjerkgård Comment :Massive chalcopyrite with lenses of pyrrhotite and sphalerite No. of registrated element analyses = 1
	BB-04	Dump	Sampler :T. Bjerkgård Comment :Coarse massive pyrite in matrix of pyrrhotite and sphalerite No. of registrated element analyses = 1
	NO0646.04	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Muskovittgneis. Bh.8109 (18,20-19,20m). No. of registrated element analyses = 1
	NO0646.05	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Massivmalm. Bh.8109 (19,20-20,15m). No. of registrated element analyses = 1
	NO0646.06	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Muskovittgneis. Bh.8109 (20,15-21,15m). No. of registrated element analyses = 1

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

Name of Locality : Skillebekk

(Object Id : 1833,070,01,00)

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Location

County :

Nordland (18)

Municipality :

Rana (1833)

Map 1:50000:

Storforshei (2027-4)

Map 1:250000:

Mo i Rana

Marking point:

Longitude:

14.3620170

Latitude:

66.2730440

EU89-UTM Zone 33

(Coordinates IS confirmed)

X-coord:

471354 m.

Y-coord:

7350490 m.

Commodity

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

Production

	Activity:	Pitting	Reserves:
	Prod. method:		Production:
	Prod. status:		Volume of dump:

Information(s) in free text format

Free text

About 400 m to the west, and possibly at a lower structural level than the Bertelberget and Heramb mineralizations, is the Skillebekk prospect. The prospect is a 12 m long and up to 2.4 m deep trench oriented N-S (across strike). It revealed a 2.7 m wide zone of pyrrhotite-pyrite mineralization with some scattered aggregates of chalcopyrite and sphalerite. Two samples from the prospect yielded 0.2-0.4 % Cu, 1.8-2.2 % Zn, < 0.01 % Pb and 1-57 g/t Ag.

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	NO0646.01	Bedrock	Sampler :Wilberg, R./...Stored :Løkken Comment :Amfibolitt. No. of registrated element analyses = 1
	NO0646.02	Bedrock	Sampler :Wilberg, R./...Stored :Løkken Comment :Massiv, granatrik, lys kvarts-feltspatbergart fra malmens heng. No. of registrated element analyses = 1
	NO0646.03	Bedrock	Sampler :Wilberg, R./...Stored :Løkken Comment :Massiv po-cpy-sl-malm. No. of registrated element analyses = 1
	SKI-01	Dump	Sampler :T. Bjerkgård Comment :Massiv py-po ore with subordinate chalcopyrite and sphalerite in aggregates 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

Deposit Area 1833 - 070 Bertelberget

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#
BB-01	Dump	1645	37000	22	30	-5	1.0	-10.0
BB-02	Dump	4200	15350	45	12	10	4.0	30.0
BB-03	Dump	115000	19900	1810	-1	-5	45.0	530.0
BB-04	Dump	8850	24200	3	25	-5	12.0	90.0
NO0646.01	Bedrock	126	142	3	11	12	.4	16.0
NO0646.02	Bedrock	74	178	14	5	1	.3	2.0
NO0646.03	Bedrock	2057	17922	2	10	25	57.5	348.0
NO0646.04	Core	762	2082	1083	8	6	19.0	213.0
NO0646.05	Core	5887	19558	239	7	5	20.5	1156.0
NO0646.06	Core	449	443	1030	3	3	48.7	563.0
SKI-01	Dump	3760	22200	32	3	-5	1.0	-10.0

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

Sample No.	Pt#	Pd#	As*	Cd*	Ba*	Mo*	Sn*	Sb*	Bi*
BB-01			723		10	4.00	1	5	8
BB-02			131		149	5.00	70	-5	-2
BB-03			187		212	7.00	154	16	57
BB-04			625		4	7.00	206	-5	7
NO0646.01	2.0	4.0	5	.2	1	1.00		2	2
NO0646.02	1.0	2.0	33	.9	5	1.00		2	2
NO0646.03	4.0	5.0	2	73.7	1	1.00		4	2
NO0646.04	9.0	1.0	48	14.3	92	1.00		3	2
NO0646.05	5.0	1.0	240	105.8	3	1.00		2	3
NO0646.06	3.0	1.0	369	3.3	57	1.00		7	3
SKI-01			147		3	9.00	4	12	9

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

Sample No.	Ga*	S%	V*	Cr*	Mn*	Fe%	Th*	U*	W*
BB-01	2.00					41.40
BB-02	21.00					26.70
BB-03	13.00					22.30
BB-04	2.00					41.40
NO0646.01		.07	54	24	441	1.70	1.00	5.00	1
NO0646.02		.15	14	6	118	1.34	1.00	5.00	1
NO0646.03		32.96	1	1	889	42.25	1.00	5.00	65
NO0646.04		1.67	43	9	590	4.11	6.00	5.00	1
NO0646.05		45.38	4	1	376	26.61	1.00	5.00	7
NO0646.06		.61	15	5	250	1.65	2.00	5.00	1
SKI-01	5.00					43.40

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

Sample No.	Sr*	La*	B*
BB-01
BB-02
BB-03
BB-04
NO0646.01	5.0	2.00	3
NO0646.02	4.0	2.00	2
NO0646.03	11.0	2.00	40
NO0646.04	3.0	9.00	2
NO0646.05	1.0	2.00	2
NO0646.06	1.0	5.00	2
SKI-01

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The fact sheet was created on 22.11.2024

Questions or comments regarding the fact sheet can be emailed to: ressursdatabaser@ngu.no

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