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Overntjern Quarry, Overntjern, Modum, Buskerud, Norwayi
Regional Level Types
Overntjern QuarryQuarry (Abandoned)
OverntjernLake
ModumMunicipality
BuskerudCounty
NorwayCountry

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PhotosMapsSearch
08468390017272004823763.jpg
Dumps

Overntjern Quarry, Overntjern, Modum, Buskerud, Norway
06341450017272004848597.jpg
Top of dump

Overntjern Quarry, Overntjern, Modum, Buskerud, Norway
08558680017272004851767.jpg
A dump at Overntjern

Overntjern Quarry, Overntjern, Modum, Buskerud, Norway
08468390017272004823763.jpg
Dumps

Overntjern Quarry, Overntjern, Modum, Buskerud, Norway
06341450017272004848597.jpg
Top of dump

Overntjern Quarry, Overntjern, Modum, Buskerud, Norway
08558680017272004851767.jpg
A dump at Overntjern

Overntjern Quarry, Overntjern, Modum, Buskerud, Norway
08468390017272004823763.jpg
Dumps

Overntjern Quarry, Overntjern, Modum, Buskerud, Norway
04018160017272004979968.jpg
Top of dump

Overntjern Quarry, Overntjern, Modum, Buskerud, Norway
Latitude & Longitude (WGS84):
59° 57' 2'' North , 9° 51' 58'' East
Latitude & Longitude (decimal):
59.95058,9.86629
GRN:
N40E04
Type:
Quarry (Abandoned) - last checked 2021
Köppen climate type:
Dfc : Subarctic climate
Nearest Settlements:
PlacePopulationDistance
Vikersund2,448 (2016)7.2km
Nakkerud350 (2013)15.1km
Prestfoss465 (2014)16.5km
Tyristrand795 (2013)19.7km
Krøderen496 (2013)19.9km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Buskerud GeologiforeningSolbergelva24km
Mindat Locality ID:
2496
Long-form identifier:
mindat:1:2:2496:2
GUID (UUID V4):
0
Other/historical names associated with this locality:
Overngruve
Other Languages:
Norwegian:
Overntjern gruve, Overntjern, Modum, Buskerud, Norge


A serpentine-magnesite deposit quarried for magnesite and serpentine.

Now abandoned.

Note: the name Overntjern is often used for the quarry (Overngruve), although Overntjern is, in fact, a small, unmined serpentinite outcrop nearby (close to the track leading to the Overngruve).

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


11 valid minerals.

Detailed Mineral List:

ⓘ Althausite
Formula: Mg4(PO4)2(OH,O)(F,◻)
Description: It is gray in color because of inclusions of magnetite and xenotime. It is also intimately associated with apatite. It occurs in cleavable masses up to several hundred grams and is altered to apatite along the cleavages.
ⓘ 'Apatite'
Formula: Ca5(PO4)3(Cl/F/OH)
Colour: brown
ⓘ Brucite
Formula: Mg(OH)2
ⓘ Clinochlore
Formula: Mg5Al(AlSi3O10)(OH)8
ⓘ Clinochlore var. Leuchtenbergite
Formula: Mg5Al(AlSi3O10)(OH)8
ⓘ Collinsite
Formula: Ca2Mg(PO4)2 · 2H2O
Description: As replacement of reddish althausite.
ⓘ Dolomite
Formula: CaMg(CO3)2
ⓘ Enstatite
Formula: Mg2Si2O6
ⓘ Hematite
Formula: Fe2O3
ⓘ Magnesite
Formula: MgCO3
Habit: massive cleavages
Colour: white, pale pink
ⓘ Phosphoellenbergerite
Formula: (Mg,◻)2Mg12(PO4,PO3OH)6(PO3OH,CO3)2(OH)6
ⓘ Pyrope
Formula: Mg3Al2(SiO4)3
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4
ⓘ Talc
Formula: Mg3Si4O10(OH)2

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘHematite4.CB.05Fe2O3
ⓘBrucite4.FE.05Mg(OH)2
Group 5 - Nitrates and Carbonates
ⓘMagnesite5.AB.05MgCO3
ⓘDolomite5.AB.10CaMg(CO3)2
Group 8 - Phosphates, Arsenates and Vanadates
ⓘAlthausite8.BB.25Mg4(PO4)2(OH,O)(F,◻)
ⓘPhosphoellenbergerite8.BB.55(Mg,◻)2Mg12(PO4,PO3OH)6(PO3OH,CO3)2(OH)6
ⓘCollinsite8.CG.05Ca2Mg(PO4)2 · 2H2O
Group 9 - Silicates
ⓘPyrope9.AD.25Mg3Al2(SiO4)3
ⓘEnstatite9.DA.05Mg2Si2O6
ⓘTalc9.EC.05Mg3Si4O10(OH)2
ⓘClinochlore9.EC.55Mg5Al(AlSi3O10)(OH)8
ⓘvar. Leuchtenbergite9.EC.55Mg5Al(AlSi3O10)(OH)8
Unclassified
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4
ⓘ'Apatite'-Ca5(PO4)3(Cl/F/OH)

List of minerals for each chemical element

HHydrogen
Hⓘ AlthausiteMg4(PO4)2(OH,O)(F,◻)
Hⓘ BruciteMg(OH)2
Hⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Hⓘ CollinsiteCa2Mg(PO4)2 · 2H2O
Hⓘ TalcMg3Si4O10(OH)2
Hⓘ Phosphoellenbergerite(Mg,◻)2Mg12(PO4,PO3OH)6(PO3OH,CO3)2(OH)6
Hⓘ Clinochlore var. LeuchtenbergiteMg5Al(AlSi3O10)(OH)8
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
Hⓘ ApatiteCa5(PO4)3(Cl/F/OH)
CCarbon
Cⓘ DolomiteCaMg(CO3)2
Cⓘ MagnesiteMgCO3
Cⓘ Phosphoellenbergerite(Mg,◻)2Mg12(PO4,PO3OH)6(PO3OH,CO3)2(OH)6
OOxygen
Oⓘ AlthausiteMg4(PO4)2(OH,O)(F,◻)
Oⓘ BruciteMg(OH)2
Oⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Oⓘ CollinsiteCa2Mg(PO4)2 · 2H2O
Oⓘ DolomiteCaMg(CO3)2
Oⓘ EnstatiteMg2Si2O6
Oⓘ HematiteFe2O3
Oⓘ MagnesiteMgCO3
Oⓘ PyropeMg3Al2(SiO4)3
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ Phosphoellenbergerite(Mg,◻)2Mg12(PO4,PO3OH)6(PO3OH,CO3)2(OH)6
Oⓘ Clinochlore var. LeuchtenbergiteMg5Al(AlSi3O10)(OH)8
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
Oⓘ ApatiteCa5(PO4)3(Cl/F/OH)
FFluorine
Fⓘ AlthausiteMg4(PO4)2(OH,O)(F,◻)
Fⓘ ApatiteCa5(PO4)3(Cl/F/OH)
MgMagnesium
Mgⓘ AlthausiteMg4(PO4)2(OH,O)(F,◻)
Mgⓘ BruciteMg(OH)2
Mgⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Mgⓘ CollinsiteCa2Mg(PO4)2 · 2H2O
Mgⓘ DolomiteCaMg(CO3)2
Mgⓘ EnstatiteMg2Si2O6
Mgⓘ MagnesiteMgCO3
Mgⓘ PyropeMg3Al2(SiO4)3
Mgⓘ TalcMg3Si4O10(OH)2
Mgⓘ Phosphoellenbergerite(Mg,◻)2Mg12(PO4,PO3OH)6(PO3OH,CO3)2(OH)6
Mgⓘ Clinochlore var. LeuchtenbergiteMg5Al(AlSi3O10)(OH)8
AlAluminium
Alⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Alⓘ PyropeMg3Al2(SiO4)3
Alⓘ Clinochlore var. LeuchtenbergiteMg5Al(AlSi3O10)(OH)8
SiSilicon
Siⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Siⓘ EnstatiteMg2Si2O6
Siⓘ PyropeMg3Al2(SiO4)3
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ Clinochlore var. LeuchtenbergiteMg5Al(AlSi3O10)(OH)8
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
PPhosphorus
Pⓘ AlthausiteMg4(PO4)2(OH,O)(F,◻)
Pⓘ CollinsiteCa2Mg(PO4)2 · 2H2O
Pⓘ Phosphoellenbergerite(Mg,◻)2Mg12(PO4,PO3OH)6(PO3OH,CO3)2(OH)6
Pⓘ ApatiteCa5(PO4)3(Cl/F/OH)
ClChlorine
Clⓘ ApatiteCa5(PO4)3(Cl/F/OH)
CaCalcium
Caⓘ CollinsiteCa2Mg(PO4)2 · 2H2O
Caⓘ DolomiteCaMg(CO3)2
Caⓘ ApatiteCa5(PO4)3(Cl/F/OH)
FeIron
Feⓘ HematiteFe2O3

Other Regions, Features and Areas containing this locality

Baltic Shield (Fennoscandian Shield)Shield
Eurasian PlateTectonic Plate
EuropeContinent
Norway
ScandinaviaRegion

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Jøsang, Ottar (1966) Geologiske og petrografiske undersøkelser i Modumfeltet [Geological and petrographic investigations in the Modum field]. Norges Geologiske Undersøkelse 235. Universitetsforlaget pp.91-97
Rømming, Christian, Raade, Gunnar (1980) The crystal structure of althausite, Mg4(PO4)2(OH,O) (F,[]) American Mineralogist, 65 (5-6) 488-498
Witsø, Tor (1994) Sjelden dolomitt fra Overtjern. STEIN. Nordisk magasin for populær geologi, 21 (3) 193
Raade, Gunnar (1999) Et unikt mineralselskap av magnesiumfosfater fra magnesitt -serpentin -forekomster på Modum [An unique mineral assemblage of magnesium phospates from magnesite-serpentine localities in Modum]. Norsk Bergverksmuseum Skrift, 15. 11-14
Nordrum, Fred Steinar (2000) Nyfunn av mineraler i Norge 1999-2000. Norsk Bergverksmuseum Skrift, 17. 59-63
Nordrum, Fred Steinar, Garmo, Torgeir T. (2006) Nyfunn av mineraler i Norge 2005-2006 [New finds of minerals in Norway 2005-2006]. Norsk Bergverksmuseum Skrift, 33. 56-62
Raade, Gunnar (2011) A metamict, thorium-rich magnesium phosphate from Overntjern, Modum, Norway. Norsk Bergverksmuseum Skrift, 46. 33-36
www.nags.net (n.d.) http://www.nags.net/Mineralsymposium/2011/2011-Raade2.pdf
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