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	Occurence 3240 - 001 Græsli, hovedbrudd, no. 1
	(Object Id: 6488) (Last updated: 01.03.2005)

Mineralization

	Era:	Proterozoic	Period:	Neoproterozoic
	Genesis:	Hydrothermal vein	Form:	Plate
	Main texture:	Fracture filling	Min. distribution:	Irregular (scattered)

Main grain size:

Medium grained (1-3 mm)

Main alteration:

Sericitisation

	Strike/Dip:	104 / 90	Direction:
			Plunge:

Stratigraphic classification of host rock

Era:

Proterozoic

Period:

Paleoproterozoic

	Province:	East Norwegian Basement Province
	Geotec.unit:	Solør Complex
	Tectonic complex:	Mylonite Zone
	Igneous complex:

Group:

Formation:

Mineralogy

	Relationship	Mineral	Amount
	Gangue mineral	Quartz	Major mineral (>10%)
	Gangue mineral	Potassic feldspar	Subordinate mineral (1-10%)
	Gangue mineral	Sericite	Subordinate mineral (1-10%)
	Ore mineral	Pyrite	Major mineral (>10%)
	Ore mineral	Chalcopyrite	Subordinate mineral (1-10%)
	Ore mineral	Gold	Accessory mineral (<1%)
	Ore mineral	Hematite	Accessory mineral (<1%)
	Ore mineral	Carrollite	Accessory mineral (<1%)
	Ore mineral	Galena	Accessory mineral (<1%)

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Joints/Fractures	Strike/Dip :68 / 90	Syn-mineralisation ;...Effect :Controls
	Host rock	Fault plane	Strike/Dip :77 / 90	Syn-mineralisation ;...Effect :Controls
	Host rock	Fault plane	Strike/Dip :90 / 90	Syn-mineralisation ;...Effect :Controls
	Host rock	Fault plane	Strike/Dip :97 / 90	Syn-mineralisation ;...Effect :Controls
	Host rock	Fault plane	Strike/Dip :104 / 90	Syn-mineralisation ;...Effect :Controls
	Host rock	Foliation	Strike/Dip :135 / 90	Pre-mineralisation
	Host rock	Shear plane	Strike/Dip :155 / 75	Pre-mineralisation ;...Effect :None
	Host rock	Shear plane	Strike/Dip :335 / 80	Pre-mineralisation ;...Effect :None

Information(s) in free text format

Free text

The Græsli mine and prospects is situated shortly west of Lake Larsputten where they occur along a 3-8 m thick and steeply-dipping quartz vein following a topographic depression over a distance of 300 m. The mines and prospects are numbered consecutively from no. 1 (Græsli mine) in the east to no. 5 in the west, where the vein bifurcates into a number of thin veins before the veins die out. The main mine comprises a more than 5 m deep shaft measuring 4 m x 8 m in cross-section. The water-filled pit at no. 5 is of comparable size, whereas the others are much smaller. The vein consists of coarsely crystalline milky quartz and is usually enveloped by 0,2-0.5 m wide zones of sericite-altered host-rocks, comprising mostly coarse-grained and megacrystic gneiss granites of the Solør Complex. The formation of the somewhat crescent-shaped vein was controlled by three interconnected systems of fractures striking NE-SW, ENE-WSW and ESE-WNW. Detailed bedrock-mapping by P. M. Ihlen has revealed the presence of a ENE-WSW-striking normal fault along the topographical depression. The fault follows the southern contact of the vein east of prospect no. 5 where the vein becomes brecciated and cemented by early amorphous carbon and late red K-feldspar. The vein is poorly mineralised and only major concentrations of sulphides are only found in pit no. 1 and no. 5. The sulphides comprising pyrite and chalcopyrite, fill interstices between quartz and K-feldspar crystals as well as fractures, partly together with amorphous carbon and K-feldspar. Microscopic examinations of sulphide samples from the Græsli mine reveal the presence of 10-50 mm grains of native gold intergrown with quartz and chalcopyrite, the latter often filling micro-fractures in pyrite. Analyses of the ores yield up to 2.3 g/t Au.

Name of Locality: Skjerp no. 2

(Object Id: 15842 1,01,00)

Location

County:

Akershus

Municipality:

Eidsvoll (3240)

Map 1:50000:

Eidsvoll (1915-1)

Map 1:250000:

Hamar

Coordinate system:

EU89-UTM Zone 32

East:

632095 m.

North:

6695865 m.

Longitude:

11.3959670

Latitude:

60.3775880

Show on map

Resource

	Resource Type:	Precious metals (Au,Ag,PGE)	Resource Subtype:	Gold
			Element(s):	Au Kis

Resources and production

	Activity:	Test mining	Reserves:
	Operating method:	Open pit mining	Historical production:

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Hydrothermal vein	Strike/Dip :97 / 90

Name of Locality: Skjerp no.3

(Object Id: 15843 1,02,00)

Location

County:

Akershus

Municipality:

Eidsvoll (3240)

Map 1:50000:

Eidsvoll (1915-1)

Map 1:250000:

Hamar

Coordinate system:

EU89-UTM Zone 32

East:

631941 m.

North:

6695791 m.

Longitude:

11.3931100

Latitude:

60.3769750

Show on map

Resource

	Resource Type:	Precious metals (Au,Ag,PGE)	Resource Subtype:	Gold
			Element(s):	Au Kis

Resources and production

	Activity:	Test mining	Reserves:
	Operating method:	Open pit mining	Historical production:

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Hydrothermal vein	Strike/Dip :77 / 90

Name of Locality: Skjerp no. 4

(Object Id: 15844 1,03,00)

Location

County:

Akershus

Municipality:

Eidsvoll (3240)

Map 1:50000:

Eidsvoll (1915-1)

Map 1:250000:

Hamar

Coordinate system:

EU89-UTM Zone 32

East:

631892 m.

North:

6695764 m.

Longitude:

11.3922050

Latitude:

60.3767570

Show on map

Resource

	Resource Type:	Precious metals (Au,Ag,PGE)	Resource Subtype:	Gold
			Element(s):	Au Kis

Resources and production

	Activity:	Test mining	Reserves:
	Operating method:	Open pit mining	Historical production:

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Hydrothermal vein	Strike/Dip :90 / 90

Name of Locality: Skjerp no. 5

(Object Id: 15845 1,04,00)

Location

County:

Akershus

Municipality:

Eidsvoll (3240)

Map 1:50000:

Eidsvoll (1915-1)

Map 1:250000:

Hamar

Coordinate system:

EU89-UTM Zone 32

East:

631853 m.

North:

6695728 m.

Longitude:

11.3914750

Latitude:

60.3764470

Show on map

Resource

	Resource Type:	Precious metals (Au,Ag,PGE)	Resource Subtype:	Gold
			Element(s):	Au Kis

Resources and production

	Activity:	Mining	Reserves:
	Operating method:	Open pit mining	Historical production:

Structures

	Location:	Type:	Orientation(360 gr.):	Relation to min.:
	Host rock	Hydrothermal vein	Strike/Dip :57 / 90

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The fact sheet was created on 26.10.2025

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