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Hercules Mine, Penobscot, Hancock County, Maine, USAi
Regional Level Types
Hercules MineMine
PenobscotTown
Hancock CountyCounty
MaineState
USACountry

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Latitude & Longitude (WGS84):
44° 25' 45'' North , 68° 44' 53'' West
Latitude & Longitude (decimal):
44.42937,-68.74822
GRN:
N30W36
Type:
Mine
Köppen climate type:
Dfb : Warm-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Penobscot1,397 (2017)4.9km
Castine1,029 (2017)6.2km
Brooksville947 (2017)10.5km
Stockton Springs1,540 (2017)10.9km
North Penobscot461 (2017)12.4km
Mindat Locality ID:
7602
Long-form identifier:
mindat:1:2:7602:2
GUID (UUID V4):
0
Other/historical names associated with this locality:
Hercules Dunbar Mine


A Pb-Zn-silica-pyrite occurrence/prospect/mine located N of Castine, on the N side of Bagaduce Narrows, in the SW corner of Tills Cove. Exposed at low tide. This locality was opened during the Maine Silver Rush of 1880. As was typical of Maine metal mines opened in the time period, the companies were failures and often had fraudulently or mistakenly identified minerals. Many of these mines were supposedly silver mines, but the only "silver" source was low-grade galena. Native silver was never found. The USGS MRDS database stated accuracy for this locality is 100 meters.

Mineralization is a polymetallic sulfide deposit (mineral occurrence model information: Model code: 184; USGS model code: 28a; deposit model name: massive sulfide, kuroko; Mark3 model number: 93).

Workings include underground openings comprised of a two-compartment shaft 80 feet deep exposed only at low tide. At high tide it is 115 ft offshore. Diamond drilled by Dennison Mines, Ltd., with Bruce Bouley, in 1964. A sulfide-bearing vein crops out 350 feet SW of the main shaft along the high tide shoreline.

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


7 valid minerals.

Detailed Mineral List:

ⓘ Chalcopyrite ?
Formula: CuFeS2
ⓘ 'Chlorite Group'
ⓘ Galena
Formula: PbS
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
ⓘ Hematite
Formula: Fe2O3
ⓘ Hematite var. Specularite
Formula: Fe2O3
ⓘ 'Mica Group'
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrrhotite ?
Formula: Fe1-xS
ⓘ Quartz
Formula: SiO2
ⓘ Sphalerite ?
Formula: ZnS

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘSphalerite ?2.CB.05aZnS
ⓘChalcopyrite ?2.CB.10aCuFeS2
ⓘPyrrhotite ?2.CC.10Fe1-xS
ⓘGalena2.CD.10PbS
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘHematite4.CB.05Fe2O3
ⓘvar. Specularite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
Unclassified
ⓘ'Chlorite Group'-
ⓘ'Mica Group'-
ⓘ'Garnet Group'-X3Z2(SiO4)3

List of minerals for each chemical element

OOxygen
Oⓘ HematiteFe2O3
Oⓘ QuartzSiO2
Oⓘ Hematite var. SpeculariteFe2O3
Oⓘ Garnet GroupX3Z2(SiO4)3
SiSilicon
Siⓘ QuartzSiO2
Siⓘ Garnet GroupX3Z2(SiO4)3
SSulfur
Sⓘ ChalcopyriteCuFeS2
Sⓘ GalenaPbS
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
Sⓘ SphaleriteZnS
FeIron
Feⓘ ChalcopyriteCuFeS2
Feⓘ HematiteFe2O3
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
Feⓘ Hematite var. SpeculariteFe2O3
CuCopper
Cuⓘ ChalcopyriteCuFeS2
ZnZinc
Znⓘ SphaleriteZnS
PbLead
Pbⓘ GalenaPbS

Other Databases

Link to USGS MRDS:10100487

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

Hussey II, Arthur and Austin, Muriel B., 1958, Maine Metal Mines and Prospects, Maine Geological Survey, pp. 53 + map plate.
USGS MRDS ID #W101737.
Emmons, William H. (1910) Some ore deposits in Maine and the Milan mine, New Hampshire. Bulletin 432. US Geological Survey doi:10.3133/b432
Rand, John R., Caldwell, Dabney W., Austin, Muriel B. (1957) Maine Pegmatite Mines and Prospects and Associated Minerals. Vol 1. Minerals Resources Index, Department of Development of Industry and Commerce. 43pp.
Austin, Muriel B. and Hussey, Arthut M. II (1958) Maine Metal Mines and Prospects, Minerals Resources Index 3, Department of Economic Development, Augusta, Maine, pp. 53 + plate.
Rand, John R. (1958) Maine Metal Mines and Prospects. Mineral Resources Index No.3, Maine Geological Survey, Department of Economic Development, 53 pages.
Morrill, P., Hinckley, W.P. (1959), Eastern Maine: Maine Mines and Minerals, Volume 2, Dillingham Natural History Museum, Naples, Maine, 80 pages.
Young, R. S. (1962), Prospect Evaluations, Hancock County, Maine: Maine Geological Survey Special Economic Studies Series 2, 113 p.
Bouley, B.A. (1978), Volcanic Stratigraphy, Stratabound Sulfide Deposits, Relative Age Relationships in The East Penobscot Bay Area: Unpublished Ph.D. Dissertation, University of Western Ontario, London, Ontario, Canada, 168 pages.
U.S. Bureau of Mines (1995), Minerals Availability System/Mineral Industry Location System (MAS/MILS), U.S. Bureau of Mines, file ID #0230090019.
(2005) Mineral Resources Data System (MRDS), US Geological Survey.
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