Norsk versjon
THE ORE DATABASE
Deposit 4614 - 007 Stordø
(Object Id: 4754)
(Last updated: 05.01.2022)

Location
County: Vestland Municipality: Stord (4614)
Map 1:50000: Fitjar (1114-1) Map 1:250000: Haugesund
Coordinate system: EU89-UTM Zone 32
East: 299267 m. North: 6633491 m.
Longitude: 5.4226550 Latitude: 59.7904410
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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: Mining Reserves:
Operating method: Underground mining Historical production: 9000 thousand tons


Products
Element/product Crude ore grade or quality Reg. date
S 23 % 28.06.2001

Operations
From - To Activity Comments
1865 - 1904 Regular production
1906 - 1968 Regular production Company/Institution :A/S Stordø Kisgruber

Mineralization
Era: Paleozoic Period: Silurian
Genesis: Volcex Form: Layer
Main texture: Banded Min. distribution: Massive (>50 % ore minerals)
Main grain size: Fine grained (< 1 mm) Main alteration:
Strike/Dip: 40 / 70 Direction:
Plunge:
Stratigraphic classification of host rock
Era: Paleozoic Period: Silurian
Province: Caledonides
Geotec.unit: Hardangerfjord Nappe Complex
Tectonic complex:
Igneous complex:
Group: Langevåg Formation: Sagvåg

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

Lithology:
Relationship Rock Origin
Wall rock Svartberg Sedimentary
Original rock :Exhalite
Metamorphic facies :Greenschist
Wall rock Jasper Sedimentary
Original rock :Jasper
Metamorphic facies :Greenschist
Wall rock Metasandstone Sedimentary
Original rock :Greywacke
Metamorphic facies :Greenschist
Wall rock Phyllite Sedimentary
Original rock :Argillaceous sediment
Metamorphic facies :Greenschist
Wall rock Greenschist Extrusive
Original rock :Basalt
Metamorphic facies :Greenschist

Structures
Location: Type: Orientation(360 gr.): Relation to min.:
Wall rock Primary layering Strike/Dip :40 / 70 Syn-mineralisation

Information(s) in free text format
Free text
The Stordø deposit is located on the Stord island, and the mine was operated from 1865 to 1968, to a depth of nearly 600 m. The total production was 9 mill.t. of fine-grained pyrite ore with a very low content of base metals, on average 40 % S and 0.26 % Zn in the "export" ore. In addition recent analyses show up to just 0.11 % Cu. The deposit consists of several layers or lenses, 5–50 m thick, over a total stratigraphic thickness of 140 m. There are massive pyrite and magnetite- and/or chert-banded ore. In addition to pyrite there are lesser amounts of pyrrhotite. The stratabound ore bodies are in the sediments of the upper part of the Silurian Langevåg Group (Mundheim Group) which consists of turbidites (green phyllite and sandstone), chert and shallow marine metabasalts of tholeiitic to alkaline character. The lower part of the group is composed of subaerial calc-alkaline volcanic rocks overlain by submarine volcaniclastic breccias, tuffs and chert.

Bibliography:
From NGU's Reference Archive:
Foslie, Steinar , 1926
Norges svovelkisforekomster.
;Norges geologiske undersøkelse;TIDSSKRIFTARTIKKEL;NGU; No.127;122 pages
Abstract:
This paper was written in English for the XIV International Geological Congress, Madrid 1926, as a part of its monograph on the Pyrite Resources of the World. The present Norwegian edition has nearly the same content. However, the geological review is a little more extensive, the production statistics have been carried a year forward, to the end of 1925, and some more illustrations are given. The English reader is referred to monograph of the Congress, as only a short statement of the contents is given here. On page 7-13 will be found a short account of the relation of pyrite deposits to the Caledonian mountain chain in Norway. The author maintains, that the main part of its intrusives, and with them the pyrite deposits, belong to the first period of folding processes of the Norwegian mountain chain, probably of Lower Ordovician age. On page 13-18, the characteristic features of the Norwegian pyrite deposits are described, and a summary of the recent views concerning their geology is given. According to these, a small group of pyrite deposits are bio-chemical sediments between basaltic, submarine lava beds, the greatest part of them are magmatic differentiates from gabbroidal intrusives, and a last group are hydromagmatic or hydrothermal deposits.

Munster, C.A. , 1911
Stordø kisfelt.
;Norges geologiske undersøkelse;FAGRAPPORT;Bergarkivet; No.BA 1461;18 pages
Abstract:
Rapporten beskriver geologi, de forskjellige malmtyper, gir kjemiske analyser og drøfter malmkvalitet. Grubene ligger i fyllitt, og selve malmen som er svovelkis (uhyre lite magnetkis) forekommer i ganger av såkalt svartfjell. Dette deles igjen inn i flintfjell og egentlig svartfjell (man får inntrykk av at det er chert). Analyser viser ca. 90% Si02 og det er bitiminøst. Selve malmen inneholder 40 % S, ca 40 % Fe og ca. 4 % C. Forsøk viser at karbonet har lite å si for malmkvaliteten. Det er svært lite Cu og andre forventede metaller i malmen.

Egge, A.; Munster, C.A. , 1909
Rapport over kisforekomstene ved Guldberg, Lilleguldberg og Lerbanken ved Lervik, Stordø i Søndhordaland.
;Norges geologiske undersøkelse;FAGRAPPORT;Bergarkivet; No.BA 2087;7 pages
Abstract:
Rapporten består av 5-6 rapporter, brev og analyser fra Guldberg. Det framgår at det er mange skjerp i området og fordi det under drift på ett av dem (Guldberg) ble funnet en kobbermalm med dimensjoner 34x12x8m. Denne malm mistet man så (forkastning?) og man håper å finne fortsettelsen. Malmen var rik: 4% Cu, 41 % S men det blir uansett snakk om små tonnasjer. Det er foretatt en slags (EM?) måling uten å finne mer malm. Et par nye gjennomsnittsanalyser fra Guldberg og Dokken (et nærliggende skjerp) ga gehalter på 2,8 og 2,2% Cu.

Munster, C.A. , 1906
Rapport over Stordø svovelkisforekomster.
;Norges geologiske undersøkelse;FAGRAPPORT;Bergarkivet; No.BA 3685;74 pages
Abstract:
Rapporten gir en meget god oversikt over forholdene ved gruvene fram til 1906, samt detaljerte planer for driften i årene etterpå. Både tidligere eierforhold og produksjon gjennomgås nøye. Deretter kommer to kapitler om geologi og malm som er det samme som rapport nr. 1431 (s.d.), samt detaljert beskrivelse av de enkelte forekomster. Siste halvdel av rapporten går med til planene for framtidig drift. Malmen er altså svovelkis om inneholder ca. 2,2% bitumen. Eksportmalm har ca. 40% S. Produksjonen var beregnet til 70 000 t. pr. år.

References not to be found in NGU's Reference Archive.:
Bergverkenes Landssammenslutning gjennom 50 år, 1907-1957

Fieldsamples
Sample No. Sample type Miscellanrous
HO0065.01 Bedrock
Sampler: Wulff, P./...Stored: Løkken
Comment: Ekstremt fink. py-malm med årer.
No. of registrated element analyses = 1
HO0065.02 Bedrock
Sampler: Wulff, P./...Stored: Løkken
Comment: Ekstremt fink. py-malm med årer.
No. of registrated element analyses = 1
HO0065.03 Bedrock
Sampler: Wulff, P./...Stored: Løkken
Comment: Ekstremt fink. py-malm med "durchbewegung", med årer.
No. of registrated element analyses = 1
HO0065.04 Bedrock
Sampler: Wulff, P./...Stored: Løkken
Comment: Ekstremt fink. py-malm med årer.
No. of registrated element analyses = 1
HO0065.05 Bedrock
Sampler: Wulff, P./...Stored: Løkken
Comment: Skifer med 30 % mm- til cm-tykke py-lag, "sheared" lagparallelt, enkelte kvartsslirer.
No. of registrated element analyses = 1
HO0065.06 Bedrock
Sampler: Wulff, P./...Stored: Løkken
Comment: Ekstremt fink. py-malm, med avlange, parallelt orienterte py-aggregater.
No. of registrated element analyses = 1
HO0065.07 Bedrock
Sampler: Wulff, P./...Stored: Løkken
Comment: Ekstremt fink. py-malm, med noen årer.
No. of registrated element analyses = 1
HO0065.08 Bedrock
Sampler: Wulff, P./...Stored: Løkken
Comment: Ekstremt fink. py-malm med ca. 5 % po.
No. of registrated element analyses = 1
HO0065.09 Bedrock
Sampler: Wulff, P./...Stored: Løkken
Comment: Ekstremt fink. py-malm med avlange, parallelt orienterte py-aggregater. Mer "sheared" enn 06.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:


Analyse Results
from
Deposit Area 4614 - 007 Stordø

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#
HO0065.01 Bedrock 1109 402 371 118 341 .8 284.0
HO0065.02 Bedrock 524 378 203 15 142 1.2 160.0
HO0065.03 Bedrock 676 399 78 13 103 .3 27.0
HO0065.04 Bedrock 225 385 40 -1 74 .3 22.0
HO0065.05 Bedrock 155 303 25 4 41 1.4 7.0
HO0065.06 Bedrock 586 648 130 30 129 -.3 25.0
HO0065.07 Bedrock 208 320 62 4 81 .4 26.0
HO0065.08 Bedrock 350 525 152 31 130 -.3 39.0
HO0065.09 Bedrock 274 291 76 9 110 .3 32.0
------------------
Sample No. Pt# Pd# Rh# As* Cd* Ba* Mo* Sb* Bi*
HO0065.01 9.0 6.0 -5.0 1412 2.3 7 22.00 10 20
HO0065.02 7.0 -3.0 -5.0 1027 2.2 4 9.00 16 9
HO0065.03 -3.0 3.0 -5.0 470 2.8 8 13.00 -2 10
HO0065.04 -3.0 3.0 -5.0 571 2.1 6 5.00 7 5
HO0065.05 3.0 -3.0 -5.0 430 2.1 9 10.00 -2 4
HO0065.06 -3.0 11.0 -5.0 729 3.9 3 24.00 5 16
HO0065.07 -3.0 -3.0 -5.0 684 2.1 2 4.00 12 5
HO0065.08 -3.0 7.0 -5.0 744 3.8 3 18.00 9 14
HO0065.09 -3.0 3.0 -5.0 843 2.7 4 9.00 10 3
------------------
Sample No. S% V* Cr* Mn* Fe% Th* U* W* Sr*
HO0065.01 34.14 56 7 2368 47.83 2.00 -5.00 -2 8.0
HO0065.02 34.39 64 14 8845 31.18 2.00 8.00 -2 19.0
HO0065.03 27.63 75 18 7677 33.03 2.00 -5.00 -2 26.0
HO0065.04 35.21 57 8 6143 27.73 -2.00 -5.00 -2 9.0
HO0065.05 11.19 107 42 17594 24.71 5.00 -5.00 -2 50.0
HO0065.06 33.72 79 7 801 47.11 -2.00 -5.00 -2 6.0
HO0065.07 40.75 49 6 1047 27.83 -2.00 -5.00 -2 1.0
HO0065.08 34.70 77 7 806 44.11 -2.00 12.00 -2 4.0
HO0065.09 33.89 64 10 4006 26.39 -2.00 -5.00 -2 6.0
------------------
Sample No. La* B*
HO0065.01 1.00 -3
HO0065.02 4.00 3
HO0065.03 5.00 -3
HO0065.04 2.00 -3
HO0065.05 12.00 -3
HO0065.06 2.00 13
HO0065.07 -1.00 12
HO0065.08 1.00 11
HO0065.09 1.00 10


The fact sheet was created on 24.01.2022

Questions or comments regarding the fact sheet can be emailed to:
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