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THE ORE DATABASE
Occurence 1824 - 031 Dolstadåsen IV
(Object Id: 2904)
(Last updated: 28.04.2020)

Location
County: Nordland Municipality: Vefsn (1824)
Map 1:50000: Fustvatnet (1926-4) Map 1:250000: Mosjøen
Coordinate system: EU89-UTM Zone 33
East: 419930 m. North: 7304677 m.
Longitude: 13.2457100 Latitude: 65.8532980
Show on map

Resource
Resource Type: Ferrous metals(Fe, Mn, Ti) Resource Subtype: Iron
Element(s): Fe
Importance
Raw material meaning: Little Importance (reg. 18.02.2015)

Resources and production
Activity: Test mining Reserves:
Operating method: Underground mining Historical production: ,2 thousand tons


Operations
From - To Activity Comments
1940 - 1940 Geophysics

Mineralization
Era: Paleozoic Period:
Genesis: Volcex Form: Layer
Main texture: Banded Min. distribution: Semi-massive (20-50 % ore minerals)
Main grain size: Fine grained (< 1 mm) Main alteration: Epidotisation
Strike/Dip: 20 / 90 Direction:
Plunge:
Stratigraphic classification of host rock
Era: Paleozoic Period:
Province: Caledonides
Geotec.unit: Helgeland Nappe Complex
Tectonic complex: Øverste allokton
Igneous complex:
Group: Formation: Skjervenheten

Mineralogy
Relationship Mineral Amount
Gangue mineral Epidote Major mineral (>10%)
Gangue mineral Amphibole Major mineral (>10%)
Gangue mineral Calcite Subordinate mineral (1-10%)
Gangue mineral Plagioclase Subordinate mineral (1-10%)
Gangue mineral Garnet Subordinate mineral (1-10%)
Gangue mineral Quartz Subordinate mineral (1-10%)
Ore mineral Magnetite Major mineral (>10%)
Ore mineral Hematite Subordinate mineral (1-10%)
Ore mineral Pyrite Accessory mineral (<1%)

Lithology:
Relationship Rock Origin
Host rock amfibolitt Extrusive
Original rock :Basalt
Metamorphic facies :Amphibolite

Structures
Location: Type: Orientation(360 gr.): Relation to min.:
Host rock Foliation Strike/Dip :20 / 90 Post-mineralisation ;...Effect :None
Host rock Primary layering Strike/Dip :20 / 90 Syn-mineralisation ;...Effect :Controls

Information(s) in free text format
Free text
Se NO0728 for historikk. Mineraliseringen er en båndet, finkornet jernformasjon lik de andre i Dolstadåsen, bortsett fra at her opptrer litt hematitt i tillegg til magnetitt og noe svovelkis. Området er overdekket, men Kvalheim (1940), som har foretatt magnetometermåling, oppgir strøklengden til 800m og mektigheten til ca.40m. Ved UTM 419980 7304920 er det drevet inn en stoll mot vest. Det er endel magnetittbånd i amfibolitten (+-epidot) i hele stollengden, mest i inngangspartiet. Prøve 01 er semimassiv magnetittmalm i amfibolitt. Iflg. Kvalheim (1940) er stollen drevet inn i de fattigste malmpartier langs liggen. Jernformasjonen gjennomveves av endel cm-tykke hornblendetonalittårer. Hornblendetonalitt er blottet ca. 100m øst for stollen.

Bibliography:
From NGU's Reference Archive:
Remmen, K. , 1922
Kortfattede opplysninger vedkommende Chr. Ankers dødsbos grubefelter.
;Norges geologiske undersøkelse;FAGRAPPORT;Bergarkivet; No.BA 911;8 pages
Abstract:
Dokumentet gir opplysninger om grubefeltene tilhørende Chr. Ankers dødsbo. Feltene er: I Nordland: Saltdalens kobberfelter (Ingeborg, Baldoivi og Stålhaugen), Gjærvalens kobberfelter, Selvåg jernfelt, Hjeldsand jernfelt og Halsåsen- Høgåsen jernfelt. I Troms: Skogfjord Svovelkisfelt. I Finnmark: Sløkdalens kobberfelt. Med i dødsboet men ikke beskrevet her er to jernmalmanvisninger på Dønnes, Helgeland og en anvisning i Vaddasgaisa.

Fieldsamples
Sample No. Sample type Miscellanrous
DOL-4-C Bedrock
Sampler: P.M. Ihlen
Comment: Finkornet foliert magnetittmalm med sulfiddisseminasjon
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
DOL-4-D Bedrock
Sampler: P.M. Ihlen
Comment: Fk semi-massiv mt.malm fink sulf. diss og striper og brunt gnt b†nd
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
DOL-4-E Bedrock
Sampler: P.M. Ihlen
Comment: M›rkt gr›nlig fink semi-massiv mt-malm med cm-bred granitt-slire
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
NO0801.01 Bedrock
Sampler: Wilberg, R./...Stored: Løkken
Comment: Fink. amf. med semimassiv mt-min.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:


Analyse Results
from
Deposit Area 1824 - 031 Dolstadåsen IV

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#
DOL-4-C Bedrock 6 45 0 16 14 -.5
DOL-4-D Bedrock 12 28 0 19 17 .6
DOL-4-E Bedrock 35 15 1 19 10 2.2
NO0801.01 Bedrock 16 38 3 25 22 .1 2.0
------------------
Sample No. Pt# Pd# As* Cd* Ba* Mo* Sn* Sb* Bi*
DOL-4-C 1 13 0.60 2
DOL-4-D 2 19 0.60 2
DOL-4-E 4 42 0.50 1
NO0801.01 3.0 3.0 2 .2 3 1.00 2 2
------------------
Sample No. Se* Ga* S% V* Cr* Mn* Fe% Th* U*
DOL-4-C -0.50 11.40 184 0.60 0.20
DOL-4-D -0.50 11.20 120 0.80 0.20
DOL-4-E 0.70 14.70 169 0.90 0.20
NO0801.01 .37 57 41 877 18.17 2.00 5.00
------------------
Sample No. W* Rb* Sr* Y* Zr* Nb* Ta* Cs* La*
DOL-4-C -1 3.2 282.2 12.4 45 1.60 0.10 0.40 11.30
DOL-4-D -1 1.5 279.7 21.7 56 2.10 0.10 -0.10 13.10
DOL-4-E -1 4.3 690.2 25.1 68 1.60 0.10 0.20 11.10
NO0801.01 1 63.0 5.00
------------------
Sample No. Ce* Pr* Nd* Sm* Eu* Gd* Tb* Dy* Ho*
DOL-4-C 23.00 2.82 12.10 2.59 0.57 2.57 0.39 2.33 0.45
DOL-4-D 34.60 4.52 20.10 4.49 0.84 4.45 0.69 4.11 0.83
DOL-4-E 29.00 4.31 21.30 4.82 1.15 5.37 0.83 4.94 0.99
NO0801.01
------------------
Sample No. Er* Tm* Yb* Lu* B* Be* Hf*
DOL-4-C 1.37 0.20 1.31 0.23 -1 1.30
DOL-4-D 2.44 0.32 2.12 0.36 -1 1.80
DOL-4-E 2.67 0.38 2.36 0.38 -1 2.10
NO0801.01 2

Oxide analyses

( All values are in % )
Sample No. Sample Type SiO2 Al2O3 TiO2 Fe2O3 MnO MgO CaO
DOL-4-C Bedrock 32.30 2.93 0.45 42.80 0.68 5.75 14.80
DOL-4-D Bedrock 33.30 3.42 0.65 39.70 0.69 6.20 15.10
DOL-4-E Bedrock 42.50 8.69 0.92 19.70 0.35 8.18 17.40
------------------
Sample No. Na2O K2O P2O5 Loss Sum
DOL-4-C 0.42 0.03 0.38 -1.01 100.00
DOL-4-D 0.53 0.08 0.61 -0.84 99.00
DOL-4-E 0.77 0.16 0.42 0.39 99.00


The fact sheet was created on 18.10.2021

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