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THE ORE DATABASE
Occurence 5043 - 020 Langtjønna
(Object Id: 258)
(Last updated: 16.05.2006)
Location
County: Trøndelag Municipality: Raarvihke (5043)
Map 1:50000: Skorovatn (1824-2) Map 1:250000: Grong
Coordinate system: EU89-UTM Zone 33
East: 412262 m. North: 7166719 m.
Longitude: 13.1656540 Latitude: 64.6141200
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Resource
Resource Type: Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) Resource Subtype: Sulphides
Element(s): Kis
Importance
Raw material meaning: Little Importance (reg. 18.02.2015)

Resources and production
Activity: Pitting Reserves:
Operating method: Historical production:


Operations
From - To Activity Comments
1971 - 1977 Geology Company/Institution :Elkem A/S
1981 - 1982 Geophysics Company/Institution :Elkem A/S
1982 - 1982 Pitting Company/Institution :Elkem A/S
1991 - 1991 Sampling Company/Institution :NGU
1995 - 1995 Sampling Company/Institution :NGU

Mineralization
Era: Paleozoic Period: Ordovician
Genesis: Volcex Form: Irregular
Main texture: Structureless Min. distribution: Disseminated (<20 % ore minerals)
Main grain size: Fine grained (< 1 mm) Main alteration: Sericitisation
Strike/Dip: 80 / 50 Direction:
Plunge:
Stratigraphic classification of host rock
Era: Paleozoic Period: Ordovician
Province: Caledonides
Geotec.unit: Køli Nappe Complex
Tectonic complex: Gjersvik Nappe
Igneous complex:
Group: Gjersvik Formation:

Mineralogy
Relationship Mineral Amount
Gangue mineral Quartz Major mineral (>10%)
Gangue mineral Chlorite Subordinate mineral (1-10%)
Ore mineral Pyrrhotite Major mineral (>10%)
Ore mineral Pyrite Major mineral (>10%)
Ore mineral Magnetite Subordinate mineral (1-10%)
Ore mineral Chalcopyrite Accessory mineral (<1%)

Lithology:
Relationship Rock Origin
Wall rock Quartz keratophyre Extrusive
Original rock :Rhyodacite
Metamorphic facies :Greenschist
Wall rock Greenstone Extrusive
Original rock :Basalt
Metamorphic facies :Greenschist

Structures
Location: Type: Orientation(360 gr.): Relation to min.:
Wall rock Foliation Strike/Dip :66 / 30 Post-mineralisation ;...Effect :Modifies
Wall rock Mineral banding Strike/Dip :270 / 65 Post-mineralisation ;...Effect :Modifies

Information(s) in free text format
Free text
Forekomsten ligger ca. 3 km SSØ for Skorovas, 5-600 m sør for Langtjern. Hovedskjerpet ligger ved et lite tjern ved kote 660 og består av en 8 m lang røsk som er orientert nord-sør. Langtjønna-feltet ligger på grensen mellom en putelava i syd og en mørk, klorittrik grønnstein i nord. I begge disse opptrer ekshalittiske horisonter med lyse og mørke chert-lag og sure vulkanitter. Mineraliseringene ligger i en ca. 400 m lang rustsone. Denne er knyttet til sure vulkanitter i et miljø som forøvrig består av grønnstein, chert og agglomerat. Lagserien har rett veg opp. Sulfider som er funnet er finkornet magnetkis og svovelkis og enkelte kobberkiskorn. Det er antydet at rustsonen kan representere en feedersone, med mineralisering og hydrotermal omvandling, serisittisering og silifisering. Miljøet har mange fellestrekk med det en finner rundt Skorovas-malmen. Massive sulfidlag er opptil 0.5 m mektige og magnetittbenker som er 10-40 cm mektige finnes også.

Fieldsamples
Sample No. Sample type Miscellanrous
JS95177 Bedrock
Sampler: Sandstad, J.S./...Stored: Løkken
Comment: Massive pyrrhotite ore, fine to very fine grained with pyrite veinlets and quartz veins.
No. of registrated element analyses = 1
LS91178 Bedrock
Sampler: Størseth, L.R.
Comment: Massive pyrite-pyrrhotite ore.
No. of registrated element analyses = 1
LS91179 Bedrock
Sampler: Størseth, L.R.
Comment: Massive pyrite-pyrrhotite ore.
No. of registrated element analyses = 1
LS91180 Bedrock
Sampler: Størseth, L.R.
Comment: Quartz vein with pyrrhotite dissemination.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Langtjønna
(Object Id: 6873 20,00,01)
Location
County: Trøndelag Municipality: Raarvihke (5043)
Map 1:50000: Skorovatn (1824-2) Map 1:250000: Grong
Coordinate system: EU89-UTM Zone 33
East: 412202 m. North: 7166719 m.
Longitude: 13.1644010 Latitude: 64.6141050
Show on map
Resource
Resource Type: Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) Resource Subtype: Sulphides
Element(s): Kis


Fieldsamples
Sample No. Sample type Miscellanrous
JS95173 Bedrock
Sampler: Sandstad, J.S./...Stored: Løkken
Comment: Massive pyrite ore, fine grained.
No. of registrated element analyses = 1
JS95174 Bedrock
Sampler: Sandstad, J.S./...Stored: Løkken
Comment: Massive magnetite ore, fine grained, weak pyrite dissemination.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Langtjønna
(Object Id: 6874 20,00,02)
Location
County: Trøndelag Municipality: Raarvihke (5043)
Map 1:50000: Skorovatn (1824-2) Map 1:250000: Grong
Coordinate system: EU89-UTM Zone 33
East: 412212 m. North: 7166799 m.
Longitude: 13.1645610 Latitude: 64.6148250
Show on map
Resource
Resource Type: Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) Resource Subtype: Sulphides
Element(s): Kis


Fieldsamples
Sample No. Sample type Miscellanrous
JS95179 Bedrock
Sampler: Sandstad, J.S./...Stored: Løkken
Comment: quartz vein, coarse grained, hydrothermal.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Name of Sample point: Langtjønna
(Object Id: 6875 20,00,03)
Location
County: Trøndelag Municipality: Raarvihke (5043)
Map 1:50000: Skorovatn (1824-2) Map 1:250000: Grong
Coordinate system: EU89-UTM Zone 33
East: 412157 m. North: 7166759 m.
Longitude: 13.1634360 Latitude: 64.6144520
Show on map
Resource
Resource Type: Base metals (Cu,Zn,Pb,Fe sulphides, As,Sb,Bi,Sn) Resource Subtype: Sulphides
Element(s): Kis


Fieldsamples
Sample No. Sample type Miscellanrous
JS95175 Bedrock
Sampler: Sandstad, J.S./...Stored: Løkken
Comment: pyrite dissemination in altered felsic metavolcanite
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Analyse Results
from
Deposit Area 5043 - 020 Langtjønna

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#
JS95173 Bedrock 163 438 65 -1 29 1.4 94.0
JS95174 Bedrock 83 112 24 -1 26 1.1 16.0
JS95175 Bedrock 7 5 6 1 5 -.3 7.0
JS95177 Bedrock 224 634 59 17 72 .8 11.0
JS95179 Bedrock 6 5 3 1 8 -.3 -2.0
LS91178 Bedrock 311 625 68 25 61 .6 16.0
LS91179 Bedrock 214 326 60 14 45 2.8 72.0
LS91180 Bedrock 91 38 5 4 16 .1 12.0
------------------
Sample No. Pt# Pd# As* Cd* Ba* Mo* Sb* Bi* S%
JS95173 -3.0 3.0 924 1.4 1 3.00 3 -2 36.20
JS95174 -3.0 -3.0 49 .3 27 7.00 -2 -2 2.38
JS95175 -3.0 -3.0 14 -.2 35 1.00 2 2 1.43
JS95177 -3.0 -3.0 1038 1.1 5 5.00 2 -2 30.10
JS95179 -3.0 -3.0 5 -.2 2 1.00 3 2 .16
LS91178 1.0 6.0 1721 2.5 3 1.00 6 2 29.10
LS91179 1.0 9.0 885 2.4 3 5.00 5 2 26.20
LS91180 3.0 7.0 390 .2 4 2.00 2 2 2.60
------------------
Sample No. V* Cr* Mn* Fe% Th* U* W* Sr* La*
JS95173 67 11 875 21.37 -2.00 -5.00 -2 1.0 1.00
JS95174 109 21 2265 34.94 2.00 -5.00 -2 61.0 15.00
JS95175 2 3 45 3.19 -2.00 -5.00 -2 3.0 4.00
JS95177 46 8 641 39.00 2.00 -5.00 -2 4.0 3.00
JS95179 1 5 57 .71 -2.00 -5.00 -2 2.0 2.00
LS91178 44 12 879 38.61 1.00 8.00 1 3.0 2.00
LS91179 71 39 1229 29.24 1.00 6.00 1 8.0 3.00
LS91180 16 15 156 4.58 1.00 5.00 1 4.0 3.00
------------------
Sample No. B*
JS95173 -3
JS95174 -3
JS95175 -3
JS95177 -3
JS95179 -3
LS91178 6
LS91179 2
LS91180 2

The fact sheet was created on 29.04.2024
Questions or comments regarding the fact sheet can be emailed to:
ressursdatabaser@ngu.no
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