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Twin Lead Mine, Blue Hill, Blue Hill - Castine Mining District, Hancock County, Maine, USAi
Regional Level Types
Twin Lead MineMine
Blue HillTown
Blue Hill - Castine Mining DistrictMining District
Hancock CountyCounty
MaineState
USACountry

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PhotosMapsSearch
08260310017272244444206.jpg
Copper Smelter Site, Twin Lead Mine

Twin Lead Mine, Blue Hill, Blue Hill - Castine Mining District, Hancock County, Maine, USA
02856140017272244455567.jpg
Locality Map for Twin Lead Mine

Twin Lead Mine, Blue Hill, Blue Hill - Castine Mining District, Hancock County, Maine, USA
05563490017272244454864.jpg
Shaft of Twin Lead Mine, Blue Hill, Maine.

Twin Lead Mine, Blue Hill, Blue Hill - Castine Mining District, Hancock County, Maine, USA
08260310017272244444206.jpg
Copper Smelter Site, Twin Lead Mine

Twin Lead Mine, Blue Hill, Blue Hill - Castine Mining District, Hancock County, Maine, USA
02856140017272244455567.jpg
Locality Map for Twin Lead Mine

Twin Lead Mine, Blue Hill, Blue Hill - Castine Mining District, Hancock County, Maine, USA
05563490017272244454864.jpg
Shaft of Twin Lead Mine, Blue Hill, Maine.

Twin Lead Mine, Blue Hill, Blue Hill - Castine Mining District, Hancock County, Maine, USA
08260310017272244444206.jpg
Copper Smelter Site, Twin Lead Mine

Twin Lead Mine, Blue Hill, Blue Hill - Castine Mining District, Hancock County, Maine, USA
02856140017272244455567.jpg
Locality Map for Twin Lead Mine

Twin Lead Mine, Blue Hill, Blue Hill - Castine Mining District, Hancock County, Maine, USA
Latitude & Longitude (WGS84):
44° 24' 2'' North , 68° 36' 29'' West
Latitude & Longitude (decimal):
44.40075,-68.60826
GRN:
N30W36
Type:
Mine
Köppen climate type:
Dfb : Warm-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Blue Hill943 (2017)2.3km
Brooksville947 (2017)8.5km
Sedgwick1,146 (2017)10.8km
Penobscot1,397 (2017)10.8km
Surry1,415 (2017)13.5km
Mindat Locality ID:
107372
Long-form identifier:
mindat:1:2:107372:3
GUID (UUID V4):
0


A Cu-Sn-Ag-Ni-As-pyrite(S) occurrence/mine located 2.3 km (1.4 miles) SW of Blue Hill (town). The USGS MRDS database stated accuracy for this locality is 1,000 meters.

Mineralization is a polymetallic deposit (mineral occurrence model information: Model code: 91; USGS model code: 24b; Deposit model name: Massive sulfide, Besshi (Japanese deposits); Mark3 model number: 30). The lode is approximately 10 feet wide. Local rocks include the Ordovician-Precambrian Z Ellsworth formation.

Regional geologic structures/rocks include quartzites, gneiss, and amphibolite.

Workings include surface and underground openings. A 1910 site investigation indicated that the lode had been worked open cast to a depth of 12 feet for approximately 70 feet along its strike; a three-compartment shaft reportedly 200 feet deep was observed to be flooded. There is a 28-foot crosscut on the 95-foot level and a S crosscut at 122 feet. The ruins of a smelter as well as small slag heaps on site were also noted.

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:

ⓘ Arsenopyrite
Formula: FeAsS
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Bornite
Formula: Cu5FeS4
ⓘ Cassiterite
Formula: SnO2
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ 'Chlorite Group'
ⓘ Galena
Formula: PbS
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Nickeline
Formula: NiAs
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Quartz
Formula: SiO2

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘBornite2.BA.15Cu5FeS4
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘNickeline2.CC.05NiAs
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘGalena2.CD.10PbS
ⓘPyrite2.EB.05aFeS2
ⓘArsenopyrite2.EB.20FeAsS
Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘQuartz4.DA.05SiO2
ⓘCassiterite4.DB.05SnO2
Group 9 - Silicates
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
Unclassified
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Chlorite Group'-

List of minerals for each chemical element

HHydrogen
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
OOxygen
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ CassiteriteSnO2
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
AlAluminium
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SSulfur
Sⓘ ArsenopyriteFeAsS
Sⓘ BorniteCu5FeS4
Sⓘ ChalcopyriteCuFeS2
Sⓘ GalenaPbS
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
FeIron
Feⓘ ArsenopyriteFeAsS
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ BorniteCu5FeS4
Feⓘ ChalcopyriteCuFeS2
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
NiNickel
Niⓘ NickelineNiAs
CuCopper
Cuⓘ BorniteCu5FeS4
Cuⓘ ChalcopyriteCuFeS2
AsArsenic
Asⓘ ArsenopyriteFeAsS
Asⓘ NickelineNiAs
SnTin
Snⓘ CassiteriteSnO2
PbLead
Pbⓘ GalenaPbS

Other Databases

Link to USGS MRDS:10121792

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

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

Emmons, William H. (1910) Some ore deposits in Maine and the Milan mine, New Hampshire. Bulletin 432. US Geological Survey doi:10.3133/b432 pp.31-32
Hussey II, Arthur M. [compiler] (1958), Maine Metal Mines And Prospects, Maine Geological Survey Mineral Resources Index Series No. 3: 29 (June 1, 1958).
Young, R. S. (1962), Prospect Evaluations, Hancock County, Maine: Maine Geological Survey Special Economic Studies Series 2, 113 pages
U.S. Bureau of Mines (1995), Minerals Availability System/Mineral Industry Location System (MAS/MILS), U.S. Bureau of Mines, file ID #0230090078.
(2005) Mineral Resources Data System (MRDS), US Geological Survey.
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