SUPPORT US. If mindat.org is important to you, click here to donate to our Fall 2019 fundraiser!
Log InRegister
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsBooks & Magazines
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryMineral Photography

Wheal Coates, St Agnes, Cornwall, England, UKi
Regional Level Types
Wheal CoatesMine (Inactive)
St AgnesCivil Parish
CornwallCounty
EnglandConstituent Country
UKCountry

This page kindly sponsored by Keith Compton
Key
Latitude & Longitude (WGS84):
50° 18' 19'' North , 5° 13' 49'' West
Latitude & Longitude (decimal):
UK National Grid Reference:
SW700501
Locality type:
Mine (Inactive) - last checked 2019
Köppen climate type:
Nearest Settlements:
PlacePopulationDistance
Saint Agnes2,820 (2014)2.0km
Mount Hawke1,511 (2017)3.0km
North Country773 (2017)6.2km
Portreath963 (2017)6.5km
Perranporth3,210 (2017)6.8km


The mine is famous for the highly desirable and classic pseudomorphs after Carlsbad twins of orthoclase feldspar that were found around 1828. The replacing material consists of a granular mixture of largely cassiterite and minor quartz in varying proportions. Depending on the fraction of cassiterite, the colour varies from almost black to various shades of grey. The vein where they came from (perhaps an elvan), only 3 inches wide on average, was in a soft decomposed granite and contained so much of a light red sandy matter that it was called "the sand lode" (Coon, 1933; Rudler, 1905; Reid et al., 1906).

The pseudomorphs are typically are around 2.5 cm long or less, but specimens to a maximum of 5.6 cm are known. Good examples are rare and fakes were made in the 19th century by coating appropriately shaped lead sheet with granular cassiterite (Embrey & Symes, 1987). Elsewhere, similar pseudomorphs have been found very rarely at Carn Brea Mine, Illogan and at Balleswidden Mine, St. Just (Rudler, 1905).

Select Mineral List Type

Standard Detailed Strunz Dana Chemical Elements

Commodity List

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


Mineral List


18 valid minerals. 1 erroneous literature entry.

Detailed Mineral List:

Agardite-(Ce)
Formula: CeCu6(AsO4)3(OH)6 · 3H2O
Reference: Golley, P., and Williams, R. (1995): Cornish Mineral Reference Manual. Endsleigh Publications (Truro), 104 pp.
Andalusite
Formula: Al2(SiO4)O
Reference: Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477; Golley, P., and Williams, R. (1995): Cornish Mineral Reference Manual. Endsleigh Publications (Truro), 104 pp.
Arsenopyrite
Formula: FeAsS
Reference: Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477
Bismite
Formula: Bi2O3
Reference: Collins, J.H. (1892): A Handbook to the Mineralogy of Cornwall and Devon, 2nd ed., D. Bradford Barton Ltd. (Truro, UK), 108 pp.
Bismutite
Formula: (BiO)2CO3
Description: Originally thought to be eulytine, however Clark et al. proved it to be bismutite.
Reference: Hogg, T. (1825) A Manual of Mineralogy. Polyblank Publishers (London), p. 25; Collins, J.H. (1892) A Handbook to the Mineralogy of Cornwall and Devon, 2nd ed., D. Bradford Barton Ltd. (Truro, UK), 108 pp.; Clark, A.M., Couper, A.G., Embrey, P.G., and Fejer, E.E. (1986) Mineralogical Magazine 50, 731-733.; Braithwaite, R.S.W. and Knight, J.R. (1990) Rare Minerals, Including Several New to Britain, in Supergene Alteration of U-Cu-As-Bi-Co Mineralisation Near Dalbeattie, South Scotland. Mineralogical Magazine, vol. 54, n° 374: 129-131. (referring to Clark, et al.)
Cassiterite
Formula: SnO2
Description: also as pseudomorphs after orthoclase
Reference: Reid, C., Scrivenor, J.B., Flett, J.S., Pollard, W., and MacAlister, D.A. (1906): The Geology of the Country near Newquay. HMSO Publications (London), 131 pp.; Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477; Embrey, P.G., and Symes, R.F. (1987): Minerals of Cornwall and Devon. British Museum of Natural History (London), 154 pp.; Golley, P., and Williams, R. (1995): Cornish Mineral Reference Manual. Endsleigh Publications (Truro), 104 pp.
Cassiterite var: Wood Tin
Formula: SnO2
Reference: Golley, P., and Williams, R. (1995): Cornish Mineral Reference Manual. Endsleigh Publications (Truro), 104 pp.
Chalcopyrite
Formula: CuFeS2
Reference: Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477
Copper
Formula: Cu
Reference: Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477
Cuprite
Formula: Cu2O
Reference: Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477
Eulytine
Formula: Bi4(SiO4)3
Description: A specimen from J.H. Collins in the collection of the Royal Cornwall Museum, Truro (catalogue no. 1588), is labelled as eulytine from Wheal Coates, but has been shown by Clark et al. (1986) to contain no eulytine at all, but turned out to be bismutite.
Reference: Clark, A.M., Couper, A.G., Embrey, P.G., and Fejer, E.E. (1986) Mineralogical Magazine 50, 731-733.; Braithwaite, R.S.W. and Knight, J.R. (1990) Rare Minerals, Including Several New to Britain, in Supergene Alteration of U-Cu-As-Bi-Co Mineralisation Near Dalbeattie, South Scotland. Mineralogical Magazine, vol. 54, n° 374: 129-131. (referring to Clark, et al.)
'Glauconite'
Formula: (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
Reference: Golley, P., and Williams, R. (1995): Cornish Mineral Reference Manual. Endsleigh Publications (Truro), 104 pp.
Goethite
Formula: α-Fe3+O(OH)
Reference: Paul De Bondt collection
Hematite
Formula: Fe2O3
Reference: Reid, C., Scrivenor, J.B., Flett, J.S., Pollard, W., and MacAlister, D.A. (1906): The Geology of the Country near Newquay. HMSO Publications (London), 131 pp.; Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477
Melanterite
Formula: Fe2+(H2O)6SO4 · H2O
Reference: Golley, P., and Williams, R. (1995): Cornish Mineral Reference Manual. Endsleigh Publications (Truro), 104 pp.
Orthoclase
Formula: K(AlSi3O8)
Reference: Collins, J.H. (1892): A Handbook to the Mineralogy of Cornwall and Devon, 2nd ed., D. Bradford Barton Ltd. (Truro, UK), 108 pp.
Pyrite
Formula: FeS2
Reference: Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477
Quartz
Formula: SiO2
Reference: Reid, C., Scrivenor, J.B., Flett, J.S., Pollard, W., and MacAlister, D.A. (1906): The Geology of the Country near Newquay. HMSO Publications (London), 131 pp.; Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477; Golley, P., and Williams, R. (1995): Cornish Mineral Reference Manual. Endsleigh Publications (Truro), 104 pp.
Schorl
Formula: Na(Fe2+3)Al6(Si6O18)(BO3)3(OH)3(OH)
Reference: Collins, J.H. (1892): A Handbook to the Mineralogy of Cornwall and Devon, 2nd ed., D. Bradford Barton Ltd. (Truro, UK), 108 pp.; Reid, C., Scrivenor, J.B., Flett, J.S., Pollard, W., and MacAlister, D.A. (1906): The Geology of the Country near Newquay. HMSO Publications (London), 131 pp.
Svanbergite
Formula: SrAl3(PO4)(SO4)(OH)6
Reference: Embrey, P.G., and Symes, R.F. (1987): Minerals of Cornwall and Devon. British Museum of Natural History (London), p. 51
Tenorite
Formula: CuO
Reference: Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477
'Tourmaline'
Formula: A(D3)G6(Si6O18)(BO3)3X3Z
Reference: Dines, H.G. (1956): The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
Copper1.AA.05Cu
Group 2 - Sulphides and Sulfosalts
Arsenopyrite2.EB.20FeAsS
Chalcopyrite2.CB.10aCuFeS2
Pyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
Bismite4.CB.60Bi2O3
Cassiterite4.DB.05SnO2
var: Wood Tin4.DB.05SnO2
Cuprite4.AA.10Cu2O
Goethite4.00.α-Fe3+O(OH)
Hematite4.CB.05Fe2O3
Quartz4.DA.05SiO2
Tenorite4.AB.10CuO
Group 5 - Nitrates and Carbonates
Bismutite5.BE.25(BiO)2CO3
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
Melanterite7.CB.35Fe2+(H2O)6SO4 · H2O
Group 8 - Phosphates, Arsenates and Vanadates
Agardite-(Ce)8.DL.15CeCu6(AsO4)3(OH)6 · 3H2O
Svanbergite8.BL.05SrAl3(PO4)(SO4)(OH)6
Group 9 - Silicates
Andalusite9.AF.10Al2(SiO4)O
Eulytine ?9.AD.40Bi4(SiO4)3
Orthoclase9.FA.30K(AlSi3O8)
Schorl9.CK.05Na(Fe2+3)Al6(Si6O18)(BO3)3(OH)3(OH)
Unclassified Minerals, Rocks, etc.
'Glauconite'-(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
'Tourmaline'-A(D3)G6(Si6O18)(BO3)3X3Z

List of minerals arranged by Dana 8th Edition classification

Group 1 - NATIVE ELEMENTS AND ALLOYS
Metals, other than the Platinum Group
Copper1.1.1.3Cu
Group 2 - SULFIDES
AmBnXp, with (m+n):p = 1:1
Chalcopyrite2.9.1.1CuFeS2
AmBnXp, with (m+n):p = 1:2
Arsenopyrite2.12.4.1FeAsS
Pyrite2.12.1.1FeS2
Group 4 - SIMPLE OXIDES
A2X
Cuprite4.1.1.1Cu2O
AX
Tenorite4.2.3.1CuO
A2X3
Bismite4.3.10.2Bi2O3
Hematite4.3.1.2Fe2O3
AX2
Cassiterite4.4.1.5SnO2
Group 6 - HYDROXIDES AND OXIDES CONTAINING HYDROXYL
XO(OH)
Goethite6.1.1.2α-Fe3+O(OH)
Group 16a - ANHYDROUS CARBONATES CONTAINING HYDROXYL OR HALOGEN
Bismutite16a.3.5.1(BiO)2CO3
Group 29 - HYDRATED ACID AND NORMAL SULFATES
AXO4·xH2O
Melanterite29.6.10.1Fe2+(H2O)6SO4 · H2O
Group 43 - COMPOUND PHOSPHATES, ETC.
Anhydrous Compound Phosphates, etc·, Containing Hydroxyl or Halogen
Svanbergite43.4.1.6SrAl3(PO4)(SO4)(OH)6
Group 51 - NESOSILICATES Insular SiO4 Groups Only
Insular SiO4 Groups Only with cations in >[6] coordination
Eulytine ?51.5.4.1Bi4(SiO4)3
Group 52 - NESOSILICATES Insular SiO4 Groups and O,OH,F,H2O
Insular SiO4 Groups and O, OH, F, and H2O with cations in [4] and >[4] coordination
Andalusite52.2.2b.1Al2(SiO4)O
Group 61 - CYCLOSILICATES Six-Membered Rings
Six-Membered Rings with borate groups
Schorl61.3.1.10Na(Fe2+3)Al6(Si6O18)(BO3)3(OH)3(OH)
Group 71 - PHYLLOSILICATES Sheets of Six-Membered Rings
Sheets of 6-membered rings with 2:1 layers
'Glauconite'71.2.2a.5(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
Group 75 - TECTOSILICATES Si Tetrahedral Frameworks
Si Tetrahedral Frameworks - SiO2 with [4] coordinated Si
Quartz75.1.3.1SiO2
Group 76 - TECTOSILICATES Al-Si Framework
Al-Si Framework with Al-Si frameworks
Orthoclase76.1.1.1K(AlSi3O8)
Unclassified Minerals, Mixtures, etc.
Agardite-(Ce)-CeCu6(AsO4)3(OH)6 · 3H2O
Cassiterite
var: Wood Tin
-SnO2
'Tourmaline'-A(D3)G6(Si6O18)(BO3)3X3Z

List of minerals for each chemical element

HHydrogen
H Glauconite(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
H MelanteriteFe2+(H2O)6SO4 · H2O
H SvanbergiteSrAl3(PO4)(SO4)(OH)6
H SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
H Agardite-(Ce)CeCu6(AsO4)3(OH)6 · 3H2O
H Goethiteα-Fe3+O(OH)
BBoron
B SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
B TourmalineA(D3)G6(Si6O18)(BO3)3X3Z
CCarbon
C Bismutite(BiO)2CO3
OOxygen
O AndalusiteAl2(SiO4)O
O BismiteBi2O3
O CassiteriteSnO2
O Glauconite(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
O MelanteriteFe2+(H2O)6SO4 · H2O
O OrthoclaseK(AlSi3O8)
O SvanbergiteSrAl3(PO4)(SO4)(OH)6
O Cassiterite (var: Wood Tin)SnO2
O SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
O Bismutite(BiO)2CO3
O Agardite-(Ce)CeCu6(AsO4)3(OH)6 · 3H2O
O QuartzSiO2
O TourmalineA(D3)G6(Si6O18)(BO3)3X3Z
O HematiteFe2O3
O CupriteCu2O
O TenoriteCuO
O Goethiteα-Fe3+O(OH)
O EulytineBi4(SiO4)3
NaSodium
Na Glauconite(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
Na SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
MgMagnesium
Mg Glauconite(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
AlAluminium
Al AndalusiteAl2(SiO4)O
Al Glauconite(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
Al OrthoclaseK(AlSi3O8)
Al SvanbergiteSrAl3(PO4)(SO4)(OH)6
Al SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
SiSilicon
Si AndalusiteAl2(SiO4)O
Si Glauconite(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
Si OrthoclaseK(AlSi3O8)
Si SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
Si QuartzSiO2
Si TourmalineA(D3)G6(Si6O18)(BO3)3X3Z
Si EulytineBi4(SiO4)3
PPhosphorus
P SvanbergiteSrAl3(PO4)(SO4)(OH)6
SSulfur
S MelanteriteFe2+(H2O)6SO4 · H2O
S SvanbergiteSrAl3(PO4)(SO4)(OH)6
S PyriteFeS2
S ArsenopyriteFeAsS
S ChalcopyriteCuFeS2
KPotassium
K Glauconite(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
K OrthoclaseK(AlSi3O8)
FeIron
Fe Glauconite(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
Fe MelanteriteFe2+(H2O)6SO4 · H2O
Fe SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
Fe HematiteFe2O3
Fe PyriteFeS2
Fe ArsenopyriteFeAsS
Fe ChalcopyriteCuFeS2
Fe Goethiteα-Fe3+O(OH)
CuCopper
Cu CopperCu
Cu Agardite-(Ce)CeCu6(AsO4)3(OH)6 · 3H2O
Cu ChalcopyriteCuFeS2
Cu CupriteCu2O
Cu TenoriteCuO
AsArsenic
As Agardite-(Ce)CeCu6(AsO4)3(OH)6 · 3H2O
As ArsenopyriteFeAsS
SrStrontium
Sr SvanbergiteSrAl3(PO4)(SO4)(OH)6
SnTin
Sn CassiteriteSnO2
Sn Cassiterite (var: Wood Tin)SnO2
CeCerium
Ce Agardite-(Ce)CeCu6(AsO4)3(OH)6 · 3H2O
BiBismuth
Bi BismiteBi2O3
Bi Bismutite(BiO)2CO3
Bi EulytineBi4(SiO4)3

Geochronology

Geologic TimeRocks, Minerals and Events
Phanerozoic
 Paleozoic
  Permian
   Guadalupian
ⓘ Major polymetallic mineralization~270 MaCornwall, England, UK
   Cisuralian
ⓘ Porphyry dikes intruded (latest age)~275 MaCornwall, England, UK
ⓘ Greisenization (latest age)~280 MaCornwall, England, UK
ⓘ Porphyry dikes intruded (earliest age)~280 MaCornwall, England, UK
ⓘ Formation of metallized pegmatites~285 MaCornwall, England, UK
ⓘ Greisenization (earliest age)~285 MaCornwall, England, UK
ⓘ Emplacement of major plutons~295 MaCornwall, England, UK

References

Sort by

Year (asc) Year (desc) Author (A-Z) Author (Z-A)
Rudler, F.W. (1905) A Handbook to a collection of the Minerals of the British Islands, mostly selected from the Ludlam Collection. HMSO Publications (London), 241 pp.
Reid, C., Scrivenor, J.B., Flett, J.S., Pollard, W., and MacAlister, D.A. (1906) The Geology of the Country near Newquay. HMSO Publications (London), 131 pp.
Coon, J. M. (1933) Pseudomorphs of cassiterite, etc., after feldspar at Wheal Coates, St. Agnes, Cornwall. Transactions of the Royal Geological Society of Cornwall 16(6), 297-310.
Dines, H.G. (1956) The metalliferous mining region of south-west England. HMSO Publications (London), Vol. 1, pp. 476-477.
Sharpe, A. & Smith, J. R. (1986) Wheal Coates, St. Agnes: An Archaeological Survey for the National Trust. Cornwall Archaeological Unit, Cornwall County Council (Truro).
Clark, A.M., Couper, A.G., Embrey, P.G., and Fejer, E.E. (1986) Waylandite: New Data from an Occurrence in Cornwall, and a Note on 'Agnesite'. Mineralogical Magazine 50, 731-733. [disproves the occurrence of eulytine].
Embrey, P.G., and Symes, R.F. (1987) Minerals of Cornwall and Devon. British Museum of Natural History (London), p. 69.
Rocks & Minerals 16, 129.

Mindat Articles

Pseudomorphous crystals of oxide of tin, found in Huel Coates mine, in St. Agnes by Jolyon & Katya Ralph


External Links


Other Regions, Features and Areas containg this locality

British 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.
 
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Public Relations by Blytheweigh.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2019, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: October 16, 2019 13:03:37
Go to top of page