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THE INDUSTRIAL MINERAL DATABASE
Occurence 4626 - 301 Tælavåg
(Object Id: 7934)
(Last updated: 27.04.2007)

Location
County: Vestland Municipality: Øygarden (4626)
Map 1:50000: Fjell (1115-4) Map 1:250000: Bergen
Coordinate system: EU89-UTM Zone 32 (Coordinates NOT confirmed)
East: 277017 m. North: 6686692 m.
Longitude: 4.9694930 Latitude: 60.2556080
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Resource
Resource Type: Feldspar Resource Subtype: Pegmatitic feldspar

Importance
Raw material meaning: Little Importance (reg. 18.02.2015)

Resources and production
Activity: Mining Reserves:
Operating method: Open pit and underground mining Historical production:


Mineralization
Genesis: Form:
Main texture: Min. distribution:
Main grain size:
Strike/Dip: Direction:
Plunge:
Stratigraphic classification of host rock
Era: Period:
Province:
Geotec.unit:
Tectonic complex:
Igneous complex:
Group: Formation:

Information(s) in free text format
Free text
Two granitic K-feldspar-dominated pegmatites occur 1.5 km SW of the village Tælavåg at a peninsula belonging to the Sotra island. The larger pegmatite of ca. 100 m length and 8 to 10 m width occurs ca. 200 m W of the Øvretveit camping site. The pegmatite lens dips 5 to 20° northward. K-feldspar was mined partially underground (Tælavåg Stollen) at the eastern part of the pegmatite. The Tælavåg Stollen forms a water-filled stope about 10x10x5 m in size. The megacrystic K-feldspar is crosscut by irregular quartz veins which up to 2 m in thickness and up to 20 m long. The quartz is milky in the vein centre and becomes smoky towards the margin at the contact with K-feldspar. The pegmatite of the Tælavåg Stollen was mined between 1867 and 1930 for K-feldspar and quartz. The raw material was exported to Holland and United Kingdom for china clay production. A similar but smaller pegmatite occurs next to Øvretveit camping site. The E-W striking, 25 m long and 6 m wide quarry within this pegmatite is hosted in metagabbro. The K-feldspar-rich pegmatite contains irregular veins of smoky quartz. The approximately volume ratio of K-feldspar : quartz in the quarry is 1 : 1. The pegmatite is 50 m long and 15 m wide. Megacrystic biotite (2 x 5 x 5 cm) is common at the western end of the pegmatite. The biotite crystals are aligned in E-W direction which corresponds the striking of the pegmatite. The pegmatite body dips 5 to 20° northward. The Tælavåg pegmatite contains K-feldspar with high K2O concentration of 14.2 wt.% which represents good economic quality but the K-feldspar resources of both pegmatites are more or less exploited. The Lokøyna and Tælavåg pegmatites contain quartz of medium to high quality (5-9 ppm Al, 3-7 ppm Ti, 4-10 ppm Li). At least 5000 tons resources of medium to high purity quartz are left at the Tælavåg Stollen pegmatite, which could be of minor economic interest. There is the possibility that similar pegmatite may occur under the surface in this area.

Photo(s) from the Deposit area:
Photo no. 1 showing Tælavåg pegmatite"

Fieldsamples
Sample No. Sample type Miscellanrous
2508503 Bedrock
Sampler: Muller/...Stored: NGU
Comment: pegmatite quartz from the disused quarry at the camping site Øvretveit
No. of registrated mineral analyses = 2
2508503b Bedrock
Sampler: Muller/...Stored: NGU
Comment: pegmatitic biotite from the disused Tælavåg Stollen
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
2508503k Bedrock
Sampler: Muller/...Stored: NGU
Comment: pegmatitic K-feldspar from the disused Tælavåg Stollen
No. of registrated element analyses = 1
No. of registrated oxide analyses = 1
NB! All analyse values are shown at the end of the printout.:


Analyse Results
from
Deposit Area 4626 - 301 Tælavåg

Element analyses

( *=parts pr. million, #=parts pr.billion, Negative values means below detection limit value.)
Sample No. Sample Type Cu* Zn* Pb* Co* Ni* As* Ba*
2508503b Bedrock -10 524 28 52 32 -5 24
2508503k Bedrock -10 8 116 -5 -5 -5 326
------------------
Sample No. Mo* Sn* Sb* Ga* V* Cr* Th* U* W*
2508503b 16.00 51 17 65.00 391 40 13.00 22.00 -10
2508503k -5.00 -10 -10 -10.00 -10 -10 7.00 -10.00 -10
------------------
Sample No. Rb* Sr* Y* Zr* Nb* Ta* Cs* La* Ce*
2508503b 3836.0 6.0 -5.0 -5 261.00 71.00 411.00 -10.00 -10.00
2508503k 1026.0 83.0 -5.0 7 -5.00 -10.00 17.00 -10.00 -10.00
------------------
Sample No. Pr* Nd* Yb* Sc* Hf*
2508503b -10.00 -10.00 35.00 63.00 -10.00
2508503k -10.00 -10.00 -15.00 -10.00 -10.00

Mineral analyses

( All values are in ppm. Negative values means below detection limit value.)
Sample No. Sample Type Mineral Li Be B
2508503 Bedrock Quartz 4.600 -.100 1.100
2508503 Bedrock Quartz 4.900 -.100 1.500
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Sample No. Na Al P K Ti Fe Ge
2508503 -22.000 4.900 -6.000 -1.400 3.200 -.300 1.600
2508503 -22.000 5.200 7.600 -1.400 3.400 .300 1.600

Oxide analyses

( All values are in % )
Sample No. Sample Type SiO2 Al2O3 TiO2 Fe2O3 MnO MgO CaO
2508503b Bedrock 36.49 15.26 2.70 23.74 0.45 8.74 0.05
2508503k Bedrock 64.75 18.48 0.02 0.08 -0.01 0.03 0.07
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Sample No. Na2O K2O P2O5 Loss Sum
2508503b 0.00 8.69 0.01 1.02 97.00
2508503k 1.48 14.19 0.01 0.16 99.00


The fact sheet was created on 21.10.2021

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