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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

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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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