Norsk versjon
	THE ORE DATABASE
	Deposit Area 1833 - 098
	(Last updated 22.mar.2024)

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	45 ppm
	CU	3 %
	PB	0.2 %
	ZN	3 %

Operations

	From - To	Activity	Comments
	1910 - 1911	Test mining
	1965 - 1965	Geology
	1968 - 1968	Geology
	1976 - 1976	Geophysics
	1980 - 1981	Geology
	1982 - 1982	Core drilling
	1984 - 1984	Geophysics	Company/Institution :NGU
	2007 - 2007	Geophysics	Company/Institution :GEXCO Norge AS
			TEM (by SkyTEM)
	2008 - 2008	Core drilling	Company/Institution :GEXCO Norge AS
			Two holes to investigate deep geophysical anomaly (not found)
	2008 - 2009	Geology	Company/Institution :NGU

Mineralization

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

Main grain size:

Medium grained (1-3 mm)

Main alteration:

	Strike/Dip:	245 / 35	Direction:	270
			Plunge:	15

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	Pyrrhotite	Major mineral (>10%)
	Ore mineral	Pyrite	Subordinate mineral (1-10%)
	Ore mineral	Chalcopyrite	Subordinate mineral (1-10%)
	Ore mineral	Sphalerite	Subordinate mineral (1-10%)
	Ore mineral	Rutile	Accessory mineral (<1%)
	Ore mineral	Fahlore	Accessory mineral (<1%)
	Ore mineral	Molybdenite	Accessory mineral (<1%)
	Ore mineral	Galena	Accessory mineral (<1%)
	Ore mineral	Marcasite	Accessory mineral (<1%)
	Ore mineral	Arsenopyrite	Accessory mineral (<1%)
	Ore mineral	Limonite	Accessory mineral (<1%)

Lithology:

	Relationship	Rock	Origin
	Host rock	Muskovittgneis	Extrusive Original rock :Tuff
			Metamorphic facies :Amphibolite
	Wall rock	Lys glimmergneis	Sedimentary Original rock :Greywacke
			Metamorphic facies :Amphibolite

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Foliation	Strike/Dip :245 / 35	Post-mineralisation ;...Effect :None
	Host rock	Mineral lineation	Strike/Dip :270 / 15	Post-mineralisation ;...Effect :Controls
	Host rock	Fold axis	Strike/Dip :270 / 15	Post-mineralisation ;...Effect :Controls

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 Heramb mineralization is characterized by massive sulfide veins carrying pyrrhotite and variable amounts of pyrite, chalcopyrite and sphalerite . There are also some veins strongly enriched in coarse-grained galena. An average of 14 samples from the dump yielded 3.7 % Cu, 3.1 % Zn, 0.2 % Pb, 45 g/t Ag and 0.45 g/t Au. Test mining was carried out at Heramb in 1910 and 1911, and an adit c. 50 m long was mined. This resulted in production of 193 tons with 2.87 % Cu, 4.80 % Zn. The ore zone in the adit had a thickness of 1-2 m over the first 36 m and varied from being very copper-rich to zinc-rich. In the last 14 meters of the adit only thin veins of mineralization were encountered. According to Krefting (1911) the average of the ore over a length of 36 m was 1.2 m with 1.9 % Cu and 3.4 % Zn. In 1982 eight holes were drilled around the Heramb deposit to investigate the continuation of the sulfide-rich veins towards depth. Only three of the holes intersected partly rich sulfide veins, and restricted partly the extent of the mineralization to the north and south. The best intersections were 1.75 m at 1.8 % Cu, 4 % Zn, 20 g/t Ag (bh8208) and 5.7 m at 1.5 % Cu, 0.9 % Zn, 25 g/t Ag (including 1.2 m at 4.8 % Cu, 0.9 % Zn, 73 g/t Ag¸ bh8209). A very strong geophysical anomaly (TEM and TURAM) c. 200 m to the north of the deposit was the target for drilling in 2008 (bh4608, bh4708), but no mineralization was found. The reason for this anomaly remains unknown.

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.

Fieldsamples

	Sample No.	Sample type	Miscellanrous
	HERAMB-01	Dump	Sampler :T. Bjerkgård Comment :Massive po-py-cpy ore No. of registrated element analyses = 1
	HE-01	Dump	Sampler :T. Bjerkgård Comment :Massive py-po-sl-cpy ore No. of registrated element analyses = 1
	HE-02	Dump	Sampler :T. Bjerkgård Comment :Massive py-po-sl-cpy ore No. of registrated element analyses = 1
	HE-03	Dump	Sampler :T. Bjerkgård Comment :Massive py-po-sl-cpy ore No. of registrated element analyses = 1
	NO0725.01	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Muskovittgneis med py-po-diss. Bh. 8209 (2,70-3,10m). No. of registrated element analyses = 1
	NO0725.02	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Massiv po-cpy-sl-malm. Bh. 8209 (3,10-3,35m). No. of registrated element analyses = 1
	NO0725.03	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Muskovittgneis med py-diss. Bh. 8209 (3,35-3,90m). No. of registrated element analyses = 1
	NO0725.04	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Massiv py-po-sl-malm. Bh. 8209 (3,90-4,65m). No. of registrated element analyses = 1
	NO0725.05	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Muskovittgneis. Bh. 8209 (4,65-6,80m). No. of registrated element analyses = 1
	NO0725.06	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Massiv py-sl-po-malm. Bh. 8209 (6,80-6,95m). No. of registrated element analyses = 1
	NO0725.07	Core	Sampler :Wilberg, R./...Stored :Løkken Comment :Muskovittgneis. Bh. 8209 (6,95-8,00m). No. of registrated element analyses = 1

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

Name of Locality : Skjerp 1

(Object Id : 1833,098,01,00)

---

Location

County :

Nordland (18)

Municipality :

Rana (1833)

Map 1:50000:

Storforshei (2027-4)

Map 1:250000:

Mo i Rana

Marking point:

Longitude:

14.3316570

Latitude:

66.2742330

EU89-UTM Zone 33

(Coordinates IS confirmed)

X-coord:

469992 m.

Y-coord:

7350637 m.

Commodity

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

Production

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

Information(s) in free text format

Free text

Skjerp 1: Sprengt ut 0.5 m3 i granatglimmerskifer med enkelte mm-mektige kobberkis- og sinkblendeårer.

Name of Locality : Skjerp 2

(Object Id : 1833,098,02,00)

---

Location

County :

Nordland (18)

Municipality :

Rana (1833)

Map 1:50000:

Storforshei (2027-4)

Map 1:250000:

Mo i Rana

Marking point:

Longitude:

14.3134630

Latitude:

66.2745100

EU89-UTM Zone 33

(Coordinates IS confirmed)

X-coord:

469176 m.

Y-coord:

7350677 m.

Commodity

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

Production

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

Information(s) in free text format

Free text

Skjerp 2: Lite skjerp i glimmergneis med magnetkis.

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Analyse Results

from

Deposit Area 1833 - 098 Heramb gruve

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#
HERAMB-01	Dump	153500	85100	289	1	-5	27.0	1010.0
HE-01	Dump	4080	114500	189	2	-5	4.0	80.0
HE-02	Dump	84900	47200	504	1	-5	27.0	1850.0
HE-03	Dump	8430	74000	143	2	-5	11.0	40.0
NO0725.01	Core	3867	2726	732	14	4	57.8	401.0
NO0725.02	Core	99999	21830	42	17	6	186.9	269.0
NO0725.03	Core	1292	2879	148	2	3	8.5	47.0
NO0725.04	Core	4043	36019	27	128	8	6.1	50.0
NO0725.05	Core	304	469	56	5	2	1.0	8.0
NO0725.06	Core	79880	34096	31	222	5	65.6	126.0
NO0725.07	Core	1220	1268	421	3	2	9.6	1116.0

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

Sample No.	Pt#	Pd#	As*	Cd*	Ba*	Mo*	Sn*	Sb*	Bi*
HERAMB-01			84		41	101.00	14	28	65
HE-01					13	72.00	5
HE-02					9	34.00	6
HE-03					85	80.00	28
NO0725.01	9.0	1.0	210	17.9	20	4.00		33	7
NO0725.02	7.0	3.0	258	174.4	6	1.00		2	2
NO0725.03	7.0	4.0	106	15.1	42	1.00		4	3
NO0725.04	15.0	10.0	278	231.1	4	3.00		20	27
NO0725.05	3.0	1.0	35	2.6	54	1.00		2	2
NO0725.06	7.0	9.0	390	232.7	4	2.00		24	69
NO0725.07	6.0	4.0	82	7.7	54	1.00		3	16

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

Sample No.	Ga*	S%	V*	Cr*	Mn*	Fe%	Th*	U*	W*
HERAMB-01	10.00					29.30
HE-01	10.00				1317
HE-02	3.00				775
HE-03	24.00				2091
NO0725.01		6.15	1	3	113	8.48	1.00	5.00	5
NO0725.02		30.59	6	1	486	31.75	1.00	5.00	1
NO0725.03		2.86	6	6	196	4.25	2.00	5.00	3
NO0725.04		44.24	6	5	394	37.45	4.00	5.00	1
NO0725.05		.53	11	7	323	1.61	5.00	5.00	1
NO0725.06		34.60	7	8	505	35.13	3.00	7.00	5
NO0725.07		.91	5	5	255	2.06	11.00	5.00	1

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

Sample No.	Sr*	La*	B*
HERAMB-01
HE-01
HE-02
HE-03
NO0725.01	3.0	6.00	2
NO0725.02	1.0	2.00	4
NO0725.03	2.0	7.00	3
NO0725.04	1.0	2.00	40
NO0725.05	3.0	9.00	2
NO0725.06	1.0	3.00	32
NO0725.07	4.0	17.00	2

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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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