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Mynydd Preseli intrusions, Eglwyswrw, Pembrokeshire, Wales, UKi
Regional Level Types
Mynydd Preseli intrusionsGroup of Intrusions
EglwyswrwCommunity
PembrokeshireCounty
WalesCountry
UKCountry

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PhotosMapsSearch
07002550017272091698777.jpg
Dolerite, etc.

Mynydd Preseli intrusions, Eglwyswrw, Pembrokeshire, Wales, UK
01781820017272091703113.jpg
Dolerite, etc.

Mynydd Preseli intrusions, Eglwyswrw, Pembrokeshire, Wales, UK
07002550017272091698777.jpg
Dolerite, etc.

Mynydd Preseli intrusions, Eglwyswrw, Pembrokeshire, Wales, UK
01781820017272091703113.jpg
Dolerite, etc.

Mynydd Preseli intrusions, Eglwyswrw, Pembrokeshire, Wales, UK
07184640017272054239864.jpg
Dolerite, etc.

Mynydd Preseli intrusions, Eglwyswrw, Pembrokeshire, Wales, UK
01781820017272091703113.jpg
Dolerite, etc.

Mynydd Preseli intrusions, Eglwyswrw, Pembrokeshire, Wales, UK
Latitude & Longitude (WGS84):
51° 57' 33'' North , 4° 44' 58'' West
Latitude & Longitude (decimal):
51.95931,-4.74964
GeoHash:
G#: gchxefvkv
GRN:
N35W03
UK National Grid Reference:
SN111326
Type:
Group of Intrusions
Köppen climate type:
Cfb : Temperate oceanic climate
Nearest Settlements:
PlacePopulationDistance
Maenclochog731 (2017)5.9km
Crymych704 (2017)7.2km
Newport851 (2017)8.6km
Glandwr1,586 (2018)8.7km
Llandissilio513 (2017)11.3km
Mindat Locality ID:
73111
Long-form identifier:
mindat:1:2:73111:2
GUID (UUID V4):
0
Other/historical names associated with this locality:
Dyfed


Greenschist facies Ordovician metabasite intrusions

A general locality - Mynydd Preseli (area approx 3000 hectares)is an east-west aligned ridge (reaching its highest point at Foel Eryr at its western end to Y Foel Drygarn at its eastern end).

The overall landscape is one of open heath and bracken-covered moorland grazed by sheep. Hill slopes are rarely very steep, and the characteristic cliff and scree-slopes of other Welsh Mountain massifs are absent. Summit and slope tor-like rock outcrops are a very distinctive natural element of the Mynydd Preseli landscape. These are particularly prominent at Carn Menyn, where a spiky ridge formed by them dominates the skyline.

Preseli "bluestone" was used in the construction of Stonehenge and in the manufacture of neolithic axes outcrops at Carn Menyn and Carn Alw.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


6 valid minerals.

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ 'Chlorite Group'
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ Prehnite
Formula: Ca2Al2Si3O10(OH)2
ⓘ 'Pumpellyite Subgroup'
Formula: Ca2XAl2[Si2O6(OH)][SiO4](OH)2A
ⓘ Quartz
Formula: SiO2
ⓘ Titanite
Formula: CaTi(SiO4)O

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
Group 9 - Silicates
ⓘTitanite9.AG.15CaTi(SiO4)O
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘPrehnite9.DP.20Ca2Al2Si3O10(OH)2
ⓘAlbite9.FA.35Na(AlSi3O8)
Unclassified
ⓘ'Chlorite Group'-
ⓘ'Pumpellyite Subgroup'-Ca2XAl2[Si2O6(OH)][SiO4](OH)2A

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Hⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ PrehniteCa2Al2Si3O10(OH)2
Hⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ PrehniteCa2Al2Si3O10(OH)2
Oⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
Oⓘ QuartzSiO2
Oⓘ TitaniteCaTi(SiO4)O
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ PrehniteCa2Al2Si3O10(OH)2
Alⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ PrehniteCa2Al2Si3O10(OH)2
Siⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
Siⓘ QuartzSiO2
Siⓘ TitaniteCaTi(SiO4)O
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Caⓘ PrehniteCa2Al2Si3O10(OH)2
Caⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
Caⓘ TitaniteCaTi(SiO4)O
TiTitanium
Tiⓘ TitaniteCaTi(SiO4)O
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)

Other Regions, Features and Areas containing this locality

British and Irish IslesGroup of Islands
Eurasian PlateTectonic Plate
EuropeContinent
UK

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

Eur. Jour. Mineral. , 1993, 5, pp. 925-935.
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