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Ogof Owain Glyndwr, Moel Hebog, Beddgelert, Gwynedd, Wales, UKi
Regional Level Types
Ogof Owain GlyndwrMine (Abandoned)
Moel HebogMountain
BeddgelertCommunity
GwyneddCounty
WalesCountry
UKCountry

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Latitude & Longitude (WGS84):
53° 0' 28'' North , 4° 8' 52'' West
Latitude & Longitude (decimal):
53.00778,-4.14794
GRN:
N36W02
UK National Grid Reference:
SH559478
Type:
Mine (Abandoned) - last checked 2025
Köppen climate type:
Cfb : Temperate oceanic climate
Nearest Settlements:
PlacePopulationDistance
Garndolbenmaen101 (2012)7.2km
Porthmadog2,981 (2017)8.8km
Talysarn1,086 (2017)8.9km
Penrhyndeudraeth1,546 (2017)9.9km
Penygroes1,793 (2017)10.6km
Mindat Locality ID:
145796
Long-form identifier:
mindat:1:2:145796:7
GUID (UUID V4):
0
Other/historical names associated with this locality:
Caernarvonshire


Cream to very pale green silky asbestiform actinolite associated with calcite in a vein at Ogof [cave] Owain Glyndwr on Moel Hebog. The site is actually an old mine, about 5m deep, by 4m wide, about 60 m away from the cave. Difficult to access, high up steep east-facing gully.

A few veins up to 30mm still present, but all are wet, in places like a paste.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


2 valid minerals.

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘ Calcite
Formula: CaCO3

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 9 - Silicates
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
CCarbon
Cⓘ CalciteCaCO3
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ CalciteCaCO3
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Caⓘ CalciteCaCO3
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2

Other Regions, Features and Areas containing this locality

British and Irish IslesGroup of Islands
Eurasian PlateTectonic Plate
EuropeContinent
UK

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