Fact Sheet for Deposit Area 233

					Norsk versjon
	THE ORE DATABASE
	Deposit Area 233 - 021
	(Last updated 19.des.2022)

Name of Deposit Area : Abbortjern

(Object Id : 0233,021,00,00)

Location

County :

Akershus (02)

Municipality :

Nittedal (0233)

Map 1:50000:

Nannestad (1915-3)

Map 1:250000:

Hamar

Marking point:

Longitude:

10.9016420

Latitude:

60.1234470

EU89-UTM Zone 32

(Coordinates IS confirmed)

X-coord:

605664 m.

Y-coord:

6666679 m.

Commodity

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

Production

Activity:	Pitting	Reserves:
Prod. method:		Production:
Prod. status:		Volume of dump:	100 m3

Importance

Public: Not Assessed (reg. 18.02.2015)

Economical: Minor interest , (Confirmed 01.sep.2021 by Jan Sverre Sandstad)

Mineralization

Era: Paleozoic Period: Permian

Dating: Method:

Genesis: Skarn formation Form: Lens

Main texture: Structureless Min. distribution: Massive (>50 % ore minerals)

Main grain size: Fine grained (< 1 mm) Main alteration: Skarn formation

Strike/Dip: Direction:

Plunge:

Stratigraphic classification of host rock

Era: Paleozoic Period: Cambrian

Province: Oslo Region

Geotec.unit: Akershus Graben

Tectonic complex:

Igneous complex: Nordmarka-Hurdal Batholith

Group: Formation:

Mineralogy

Relationship Mineral Amount

Gangue mineral Pyroxene Major mineral (>10%)

Gangue mineral Amphibole Subordinate mineral (1-10%)

Ore mineral Sphalerite Major mineral (>10%)

Ore mineral Pyrrhotite Subordinate mineral (1-10%)

Ore mineral Pyrite Subordinate mineral (1-10%)

Ore mineral Chalcopyrite Accessory mineral (<1%)

Lithology:

Relationship Rock Origin

Host rock Hedenbergite skarn Sedimentary
Original rock :Limestone

Metamorphic facies :Contact

Wall rock Black schist Sedimentary
Original rock :Argillaceous sediment

Metamorphic facies :Unmetamorphosed

Wall rock Biotite hornfels Sedimentary
Original rock :Argillaceous sediment

Metamorphic facies :Contact

Structures

Location: Type: Orientation(360 gr.): Relation to min.:

Wall rock Mineral banding Strike/Dip :230 / 40 Pre-mineralisation ;...Effect :Controls

Information(s) in free text format

Free text

Forekomsten ligger i det såkalte Kirkebyfeltet som domineres av hornfels, som er omdannede kambriske til undersiluriske slambergarter med kalksteinlinser. Metasedimentene grenser med en forkastning mot proterozoiske gneiser i øst. Gruvene og skjerpene er for det meste gjenfylte og ligger langs en skråning som danner vestveggen i denne forkastningen. Koordinaten er angitt til en stollinngang som i hovedsak består av svart biotitthornfels. En ca. 1 m mektig sone med sulfidmineralisert hedenbergittskarn er synlig i en gjenfylt synk ca. 20 m vest for stollinngangen. Hovedtippen er spredt utover skråningen ca. 20-25 m lengre sør. Prøver fra denne består blant annet av massiv, finkornet sinkblende med mindre mengder blyglans, kobberkis og svovelkis. Massiv magnetkis med grovkornete årer og linser av sinkblende finnes også.

Bibliography:

From NGU's Reference Archive:

Ihlen, Peter M. , 1978

Befaring av Djupdalen og Abbortjern gruver i Kirkeby-feltet.

;Norges geologiske undersøkelse;FAGRAPPORT;NGU-rapport; No.1575/60A;5 pages

Abstract:

Malmmineraliseringene inne Djupdalen og Abbortjern gruve er knyttet til tynne kalkhorisonter på henholdsvis 10 og 1-2 meters tykkelse. Disse er omvandlet til hedenbergitt-granat skarn som fører sinkblende og magnetkis. Innenfor Abbortjern gruvefelt opptrer også kvarts-breksjeganger i prekambriske gneiser, som fører sinkblende, magnetkis, kopperkis og blyglans. De to sistnevnte mineraler er kun sporadisk anriket i skarnet. Begge malmforekomster er kontrollert av store regionale forkastninger. Mineraliseringene forekommer ujevnt fordelt langs skarnsonene og breksjegangene som generelt er for tynne til å gi håp om store malmtonnasjer.

Fieldsamples

Sample No. Sample type Miscellanrous

JS-OS2129 Dump

Sampler :Sandstad/Mansur/...Stored :Løkken/...Size(kg) :2

Comment :Massive, fine grained sphalerite+chalcopyrite+pyrite

No. of registrated element analyses = 1

JS-OS2130 Dump

Sampler :Sandstad/Mansur/...Stored :Løkken/...Size(kg) :2

Comment :Massiv, fine grained pyrrhotite with sinkblnde årer/linser

No. of registrated element analyses = 1

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

Name of Locality : Abbottjern vest

(Object Id : 0233,021,01,00)

Location

County : Akershus (02) Municipality : Nittedal (0233)

Map 1:50000: Nannestad (1915-3) Map 1:250000: Hamar

Marking point: Longitude: 10.9004340 Latitude: 60.1230960

EU89-UTM Zone 32 (Coordinates IS confirmed)

X-coord: 605598 m. Y-coord: 6666638 m.

Commodity

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

Element(s): Zn Cu Pb

Production

Activity: Pitting Reserves:

Prod. method: Production:

Prod. status: Volume of dump: 100 m3

Mineralogy

Relationship Mineral Amount

Gangue mineral Pyroxene Major mineral (>10%)

Ore mineral Sphalerite Major mineral (>10%)

Ore mineral Pyrrhotite Subordinate mineral (1-10%)

Ore mineral Galena Subordinate mineral (1-10%)

Lithology:

Relationship Rock Origin

Host rock Hedenbergite skarn Sedimentary
Original rock :Limestone

Metamorphic facies :Contact

Wall rock Biotite hornfels Sedimentary
Original rock :Argillaceous sediment

Metamorphic facies :Contact

Structures

Location: Type: Orientation(360 gr.): Relation to min.:

Wall rock Mineral banding Strike/Dip :240 / 55 Pre-mineralisation ;...Effect :Controls

Information(s) in free text format

Free text

Lokaliteten består av en dels gjenfylt dagskjæring med vegger på 10x15 m. Hornfels dominerer i veggene, men i NØ er blottet 0,5 m bred sone med sinkblende i årer og linser i brunvitrende, pyroksenskarn.

Fieldsamples

Sample No. Sample type Miscellanrous

JS-OS2128 Bedrock

Sampler :Sandstad/Mansur/...Stored :Løkken/...Size(kg) :2

Comment :Sphalerite-galena, bands/lenses in pyroxene-garnet? skarn

No. of registrated element analyses = 1

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

Analyse Results

from

Deposit Area 233 - 021 Abbortjern

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#

JS-OS2128 Bedrock 34 25000 26800 32 22 35.3 1.0

JS-OS2129 Dump 7260 243000 77 486 9 12.9 -.5

JS-OS2130 Dump 2850 112000 91 55 26 3.5 15.0

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

Sample No. Pt# Pd# As* Cd* Ba* Mo* Sn* Sb* Bi*

JS-OS2128 -2.5 1.0 1 104.0 10 0.31 1 0 80

JS-OS2129 -2.5 -.5 3 999.0 20 0.75 2 0 276

JS-OS2130 -2.5 -.5 1 558.0 20 53.30 5 1 119

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

Sample No. Se* Ga* Ge* In* S% V* Cr* Mn* Fe%

JS-OS2128 75.00 8.75 0.38 0.48 1.82 34 19 49600 10.50

JS-OS2129 94.00 8.32 0.30 142.00 9.99 43 18 3440 11.10

JS-OS2130 38.00 7.13 0.34 21.30 9.99 40 9 7680 26.60

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

Sample No. Th* W* Rb* Sr* Y* Zr* Nb* Ta* Cs*

JS-OS2128 4.38 2 0.7 202.0 13.9 31 4.60 0.30 0.49

JS-OS2129 5.17 2 22.6 21.2 16.5 28 4.40 0.31 4.46

JS-OS2130 2.80 1 2.3 62.2 15.7 14 2.90 0.18 1.56

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

Sample No. La* Ce* Li* Be* Na* Mg* Al* P* K *

JS-OS2128 12.80 21.90 4 2 400 8800 21000 400 100

JS-OS2129 13.70 25.80 1 1 100 6200 16600 360 1300

JS-OS2130 8.50 14.45 1 1 600 4200 10600 360 500

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

Sample No. Ca* Sc* Ti* Te* Hf* Re* Tl*

JS-OS2128 ###### 5.90 1400 1.76 0.90 -0 1

JS-OS2129 6600 4.70 1280 4.33 0.80 -0 0

JS-OS2130 26800 3.20 750 2.46 0.40 0 0

Era:	Paleozoic	Period:	Permian
Dating:		Method:
Genesis:	Skarn formation	Form:	Lens
Main texture:	Structureless	Min. distribution:	Massive (>50 % ore minerals)

	Province:	Oslo Region
	Geotec.unit:	Akershus Graben
	Tectonic complex:
	Igneous complex:	Nordmarka-Hurdal Batholith

Relationship	Mineral	Amount
Gangue mineral	Pyroxene	Major mineral (>10%)
Gangue mineral	Amphibole	Subordinate mineral (1-10%)
Ore mineral	Sphalerite	Major mineral (>10%)
Ore mineral	Pyrrhotite	Subordinate mineral (1-10%)
Ore mineral	Pyrite	Subordinate mineral (1-10%)
Ore mineral	Chalcopyrite	Accessory mineral (<1%)

Relationship	Rock	Origin
Host rock	Hedenbergite skarn	Sedimentary Original rock :Limestone
		Metamorphic facies :Contact
Wall rock	Black schist	Sedimentary Original rock :Argillaceous sediment
		Metamorphic facies :Unmetamorphosed
Wall rock	Biotite hornfels	Sedimentary Original rock :Argillaceous sediment
		Metamorphic facies :Contact

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Wall rock	Mineral banding	Strike/Dip :230 / 40	Pre-mineralisation ;...Effect :Controls

Sample No.	Sample Type	Cu*	Zn*	Pb*	Co*	Ni*	Ag*	Au#
JS-OS2128	Bedrock	34	25000	26800	32	22	35.3	1.0
JS-OS2129	Dump	7260	243000	77	486	9	12.9	-.5
JS-OS2130	Dump	2850	112000	91	55	26	3.5	15.0

Sample No.	Pt#	Pd#	As*	Cd*	Ba*	Mo*	Sn*	Sb*	Bi*
JS-OS2128	-2.5	1.0	1	104.0	10	0.31	1	0	80
JS-OS2129	-2.5	-.5	3	999.0	20	0.75	2	0	276
JS-OS2130	-2.5	-.5	1	558.0	20	53.30	5	1	119

Sample No.	Se*	Ga*	Ge*	In*	S%	V*	Cr*	Mn*	Fe%
JS-OS2128	75.00	8.75	0.38	0.48	1.82	34	19	49600	10.50
JS-OS2129	94.00	8.32	0.30	142.00	9.99	43	18	3440	11.10
JS-OS2130	38.00	7.13	0.34	21.30	9.99	40	9	7680	26.60

Sample No.	Th*	W*	Rb*	Sr*	Y*	Zr*	Nb*	Ta*	Cs*
JS-OS2128	4.38	2	0.7	202.0	13.9	31	4.60	0.30	0.49
JS-OS2129	5.17	2	22.6	21.2	16.5	28	4.40	0.31	4.46
JS-OS2130	2.80	1	2.3	62.2	15.7	14	2.90	0.18	1.56

Sample No.	La*	Ce*	Li*	Be*	Na*	Mg*	Al*	P*	K *
JS-OS2128	12.80	21.90	4	2	400	8800	21000	400	100
JS-OS2129	13.70	25.80	1	1	100	6200	16600	360	1300
JS-OS2130	8.50	14.45	1	1	600	4200	10600	360	500

Sample No.	Ca*	Sc*	Ti*	Te*	Hf*	Re*	Tl*
JS-OS2128	######	5.90	1400	1.76	0.90	-0	1
JS-OS2129	6600	4.70	1280	4.33	0.80	-0	0
JS-OS2130	26800	3.20	750	2.46	0.40	0	0