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Dragehullet, Torsberg, Flakvarp, Skien, Telemark, Norwayi
Regional Level Types
DragehulletCave
TorsbergHill
FlakvarpHamlet
SkienMunicipality
TelemarkCounty
NorwayCountry

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PhotosMapsSearch
08320680017272078354414.jpg
Dragehullet

Dragehullet, Torsberg, Flakvarp, Skien, Telemark, Norway
08056070017272078368303.jpg
Inside Dragehullet

Dragehullet, Torsberg, Flakvarp, Skien, Telemark, Norway
06374820017272078373594.jpg
Natrojarosite, etc.

Dragehullet, Torsberg, Flakvarp, Skien, Telemark, Norway
08320680017272078354414.jpg
Dragehullet

Dragehullet, Torsberg, Flakvarp, Skien, Telemark, Norway
08056070017272078368303.jpg
Inside Dragehullet

Dragehullet, Torsberg, Flakvarp, Skien, Telemark, Norway
06374820017272078373594.jpg
Natrojarosite, etc.

Dragehullet, Torsberg, Flakvarp, Skien, Telemark, Norway
08320680017272078354414.jpg
Dragehullet

Dragehullet, Torsberg, Flakvarp, Skien, Telemark, Norway
08056070017272078368303.jpg
Inside Dragehullet

Dragehullet, Torsberg, Flakvarp, Skien, Telemark, Norway
Latitude & Longitude (WGS84):
59° 7' 24'' North , 9° 36' 3'' East
Latitude & Longitude (decimal):
59.12341,9.60099
GeoHash:
G#: u4wb67p4z
GRN:
N40E04
Type:
Cave
Köppen climate type:
Dfb : Warm-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Herre1,356 (2013)3.1km
Porsgrunn34,377 (2017)3.7km
Skien50,595 (2016)9.6km
Langangen505 (2014)12.3km
Siljan891 (2010)19.4km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Fensfeltet GeologiforeningUlefoss24km
Mindat Locality ID:
51091
Long-form identifier:
mindat:1:2:51091:7
GUID (UUID V4):
0
Name(s) in local language(s):
Dragehullet (Bakerovnen), Torsberg, Flakvarp, Skien kommune, Telemark fylke, Norge


"Dragehullet" ("The Dragon's Hole") was first described as an old mine under Tråk, by J. Machesen in 1770. However, the cave is most probably a result of natural processes (wave erosion), some prospecting on pyrite might have been done. The cave is 10 m wide, 8-10 m high and 10 m deep.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


8 valid minerals. 1 erroneous literature entry.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ 'Chlorite Group'
ⓘ Epsomite
Formula: MgSO4 · 7H2O
ⓘ 'Feldspar Group'
ⓘ Gypsum
Formula: CaSO4 · 2H2O
ⓘ Halotrichite
Formula: FeAl2(SO4)4 · 22H2O
ⓘ Hexahydrite
Formula: MgSO4 · 6H2O
Description: Showed to be pentahydrite
ⓘ Montmorillonite
Formula: (Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
ⓘ Natrojarosite
Formula: NaFe3(SO4)2(OH)6
ⓘ Pentahydrite
Formula: MgSO4 · 5H2O
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘNatrojarosite7.BC.10NaFe3(SO4)2(OH)6
ⓘPentahydrite7.CB.20MgSO4 · 5H2O
ⓘHexahydrite ?7.CB.25MgSO4 · 6H2O
ⓘEpsomite7.CB.40MgSO4 · 7H2O
ⓘHalotrichite7.CB.85FeAl2(SO4)4 · 22H2O
ⓘGypsum7.CD.40CaSO4 · 2H2O
Group 9 - Silicates
ⓘMontmorillonite9.EC.40(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Unclassified
ⓘ'Chlorite Group'-
ⓘ'Feldspar Group'-

List of minerals for each chemical element

HHydrogen
Hⓘ EpsomiteMgSO4 · 7H2O
Hⓘ GypsumCaSO4 · 2H2O
Hⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Hⓘ HexahydriteMgSO4 · 6H2O
Hⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Hⓘ NatrojarositeNaFe3(SO4)2(OH)6
Hⓘ PentahydriteMgSO4 · 5H2O
OOxygen
Oⓘ EpsomiteMgSO4 · 7H2O
Oⓘ GypsumCaSO4 · 2H2O
Oⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Oⓘ HexahydriteMgSO4 · 6H2O
Oⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Oⓘ NatrojarositeNaFe3(SO4)2(OH)6
Oⓘ PentahydriteMgSO4 · 5H2O
Oⓘ QuartzSiO2
NaSodium
Naⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Naⓘ NatrojarositeNaFe3(SO4)2(OH)6
MgMagnesium
Mgⓘ EpsomiteMgSO4 · 7H2O
Mgⓘ HexahydriteMgSO4 · 6H2O
Mgⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Mgⓘ PentahydriteMgSO4 · 5H2O
AlAluminium
Alⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Alⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
SiSilicon
Siⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Siⓘ QuartzSiO2
SSulfur
Sⓘ EpsomiteMgSO4 · 7H2O
Sⓘ GypsumCaSO4 · 2H2O
Sⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Sⓘ HexahydriteMgSO4 · 6H2O
Sⓘ NatrojarositeNaFe3(SO4)2(OH)6
Sⓘ PentahydriteMgSO4 · 5H2O
Sⓘ PyriteFeS2
CaCalcium
Caⓘ GypsumCaSO4 · 2H2O
Caⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
FeIron
Feⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Feⓘ NatrojarositeNaFe3(SO4)2(OH)6
Feⓘ PyriteFeS2

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

nags.net (n.d.) http://nags.net/Stein/1974/Dragehullet.pdf
Dahlgren, Sven (1974) Hva er dragehullet ?. NAGS-NYTT, 1[1974] (4) 6-8
Larsen, Alf Olav (1974) Sekundære mineraler fra Porsgrunn. NAGS-NYTT, 1[1974] (2) 13
Raade, G. and Sæbø, P.C. (1990) Pentahydrite, MgS04*5H2O, from Dragehullet, Porsgrunn. Interne notater 1961-1990. Mineralogisk-Geologisk Museum, UiO, Oslo, p. 149.
Larsen, Alf Olav (1993) Gruver og skjerp i Skien [Mines and Prospects in Skien], Alf Olav Larsen. 1-72pp.60-61
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