Norsk versjon
Occurence 3007 - 025 Mastekrog
(Object Id: 6186)
(Last updated: 25.02.2005)
Belongs to the Province: Holleia

County: Viken Municipality: Ringerike (3007)
Map 1:50000: Hønefoss (1815-3) Map 1:250000: Hamar
Coordinate system: EU89-UTM Zone 32
East: 558079 m. North: 6657799 m.
Longitude: 10.0429820 Latitude: 60.0532530
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Resource Type: Ferroalloys (Cr,Ni,Co,V,Mo,W) Resource Subtype: Nickel
Element(s): Ni Cu
Raw material meaning: Little Importance (reg. 18.02.2015)

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

From - To Activity Comments

Era: Proterozoic Period: Mesoproterozoic
Genesis: Unknown Form:
Main texture: Min. distribution: Disseminated (<20 % ore minerals)
Main grain size: Main alteration:
Strike/Dip: Direction:
Stratigraphic classification of host rock
Era: Proterozoic Period: Mesoproterozoic
Province: South Norwegian Basement Province
Geotec.unit: Kongsberg Complex
Tectonic complex:
Igneous complex:
Group: Formation:

Relationship Mineral Amount
Gangue mineral Quartz Major mineral (>10%)
Gangue mineral Garnet Subordinate mineral (1-10%)
Ore mineral Pyrrhotite Major mineral (>10%)

Relationship Rock Origin
Wall rock Banded gneiss
Metamorphic facies :Amphibolite

Information(s) in free text format
Free text
The mine pit is situated right next to a tractor track about 100m W of a former sports field. The pit really is a small oblique trench following the foliation, about 3m deep with a 1H1.5m entry. There is a small 10m3 tailings heap on the lower side. Sulphides are hard to find, they occur finely dispersed fine grained pyrrhotite in a quartz rich schist with some garnet. It is said there used to be a larger pit just next to the nearest house, but that has been filled back and a new road has been put over it. That is probably the so-called Grefsrud pit described in the Norsk Hydro A/S report by Vokes & Vrålstad 1969. It is supposed to have been a 2m deep pit in pale green mica gneiss with very poor pyrite impregnation. Finally, there may have been a pit closer to the road, completely covered now.

Sample No. Sample type Miscellanrous
BU0379.01 Dump
Sampler: T. Bjerkgård/I. Henderson/...Stored: Løkken/...Size(kg): 3
Comment: Few scattered grains of pyrrhotite in quartzitic schist. Some garnet.
No. of registrated element analyses = 1
NB! All analyse values are shown at the end of the printout.:

Analyse Results
Deposit Area 3007 - 025 Mastekrog

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#
BU0379.01 Dump 53 276 11 10 33 .3 19.0
Sample No. Pt# Pd# As* Cd* Ba* Mo* Sb* Bi* S%
BU0379.01 4.0 3.0 1 .1 55 1.00 2 2 -.01
Sample No. V* Cr* Mn* Fe% Th* U* W* Sr* La*
BU0379.01 45 65 498 4.92 3.00 4.00 1 6.0 39.00
Sample No. B*
BU0379.01 2

The fact sheet was created on 26.10.2021

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