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Ammonoosuc Mining District, Grafton County, New Hampshire, USAi
Regional Level Types
Ammonoosuc Mining DistrictMining District
Grafton CountyCounty
New HampshireState
USACountry

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04307610017272028115000.jpg
Native Gold

Ammonoosuc Mining District, Grafton County, New Hampshire, USA
00441950017272028127116.jpg
Native Gold

Ammonoosuc Mining District, Grafton County, New Hampshire, USA
04307610017272028115000.jpg
Native Gold

Ammonoosuc Mining District, Grafton County, New Hampshire, USA
00441950017272028127116.jpg
Native Gold

Ammonoosuc Mining District, Grafton County, New Hampshire, USA
04307610017272028115000.jpg
Native Gold

Ammonoosuc Mining District, Grafton County, New Hampshire, USA
00441950017272028127116.jpg
Native Gold

Ammonoosuc Mining District, Grafton County, New Hampshire, USA
Latitude & Longitude (WGS84):
43° North , 71° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~56km
GRN:
N30W38
Type:
Mining District
Köppen climate type:
Dfb : Warm-summer humid continental climate
Mindat Locality ID:
9113
Long-form identifier:
mindat:1:2:9113:1
GUID (UUID V4):
0


This district stretches from Woodsville to Littleton, to the northwest and southeast of the Ammonoosuc River. Most of the deposits which were worked were hydrothermal vein deposits of sulfide minerals, often located on faults with the lodes carried in fault breccias. Numerous copper and gold mines were started in the early to mid 1800s, some of which prospered up into the late 1800s. Most of the so-called "gold mines" were actually base metal mines where gold was found as a bonus mineral, if at all.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


24 valid minerals.

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘ Almandine
Formula: Fe2+3Al2(SiO4)3
ⓘ Ankerite
Formula: Ca(Fe2+,Mg)(CO3)2
ⓘ Arsenopyrite
Formula: FeAsS
ⓘ Bornite ?
Formula: Cu5FeS4
ⓘ Calcite
Formula: CaCO3
ⓘ Chalcocite ?
Formula: Cu2S
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ Dolomite
Formula: CaMg(CO3)2
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ 'Feldspar Group'
ⓘ Galena
Formula: PbS
ⓘ Hematite
Formula: Fe2O3
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Molybdenite ?
Formula: MoS2
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Native Gold
Formula: Au
ⓘ Native Silver
Formula: Ag
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Quartz
Formula: SiO2
ⓘ Sphalerite
Formula: ZnS
ⓘ Tremolite
Formula: ◻Ca2Mg5(Si8O22)(OH)2
ⓘ Zircon
Formula: Zr(SiO4)
ⓘ Zoisite
Formula: (CaCa)(AlAlAl)O[Si2O7][SiO4](OH)

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Gold1.AA.05Au
ⓘNative Silver1.AA.05Ag
Group 2 - Sulphides and Sulfosalts
ⓘChalcocite ?2.BA.05Cu2S
ⓘBornite ?2.BA.15Cu5FeS4
ⓘSphalerite2.CB.05aZnS
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘGalena2.CD.10PbS
ⓘMolybdenite ?2.EA.30MoS2
ⓘPyrite2.EB.05aFeS2
ⓘArsenopyrite2.EB.20FeAsS
Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘHematite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘAnkerite5.AB.10Ca(Fe2+,Mg)(CO3)2
ⓘDolomite5.AB.10CaMg(CO3)2
Group 9 - Silicates
ⓘAlmandine9.AD.25Fe2+3Al2(SiO4)3
ⓘZircon9.AD.30Zr(SiO4)
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘZoisite9.BG.10(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘTremolite9.DE.10◻Ca2Mg5(Si8O22)(OH)2
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
Unclassified
ⓘ'Feldspar Group'-

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ⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Hⓘ Zoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
CCarbon
Cⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Cⓘ CalciteCaCO3
Cⓘ DolomiteCaMg(CO3)2
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Oⓘ AlmandineFe32+Al2(SiO4)3
Oⓘ CalciteCaCO3
Oⓘ DolomiteCaMg(CO3)2
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ HematiteFe2O3
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Oⓘ ZirconZr(SiO4)
Oⓘ Zoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Mgⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Mgⓘ DolomiteCaMg(CO3)2
Mgⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
AlAluminium
Alⓘ AlmandineFe32+Al2(SiO4)3
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Zoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ AlmandineFe32+Al2(SiO4)3
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Siⓘ ZirconZr(SiO4)
Siⓘ Zoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
SSulfur
Sⓘ ArsenopyriteFeAsS
Sⓘ BorniteCu5FeS4
Sⓘ ChalcopyriteCuFeS2
Sⓘ ChalcociteCu2S
Sⓘ GalenaPbS
Sⓘ MolybdeniteMoS2
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
Sⓘ SphaleriteZnS
KPotassium
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Caⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Caⓘ CalciteCaCO3
Caⓘ DolomiteCaMg(CO3)2
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Caⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Caⓘ Zoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Feⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Feⓘ ArsenopyriteFeAsS
Feⓘ AlmandineFe32+Al2(SiO4)3
Feⓘ BorniteCu5FeS4
Feⓘ ChalcopyriteCuFeS2
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ HematiteFe2O3
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
CuCopper
Cuⓘ BorniteCu5FeS4
Cuⓘ ChalcopyriteCuFeS2
Cuⓘ ChalcociteCu2S
ZnZinc
Znⓘ SphaleriteZnS
AsArsenic
Asⓘ ArsenopyriteFeAsS
ZrZirconium
Zrⓘ ZirconZr(SiO4)
MoMolybdenum
Moⓘ MolybdeniteMoS2
AgSilver
Agⓘ Native SilverAg
AuGold
Auⓘ Native GoldAu
PbLead
Pbⓘ GalenaPbS

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

www.davidrumsey.com (n.d.) https://www.davidrumsey.com/luna/servlet/detail/RUMSEY~8~1~21773~670008:Map-of-the-Ammonoosuc-Mining-Distri?title=Search+Results%3A+List_No+equal+to+%273095.018%27&thumbnailViewUrlKey=link.view.search.url&fullTextSearchChecked=&annotSearchChecked=&dateRangeSearchChecked=&showShareIIIFLink=true&helpUrl=https%3A%2F%2Fdocumentation.lunaimaging.com%2Fdisplay%2FV75D%2FLUNA%2BViewer%23LUNAViewer-LUNAViewer&showTip=false&showTipAdvancedSearch=false&advancedSearchUrl=https%3A%2F%2Fdocumentation.lunaimaging.com%2Fdisplay%2FV75D%2FSearching%23Searching-Searching
Hitchcock, Charles Henry (1878) The Geology of the Ammonoosuc Mining District, An extract from The geology of New Hampshire, v. 2, p. 272-347, v. 3, pt. 5, p. 7-49.
(2020) Gold in New Hampshire. Environmental Fact Sheet GEO-1. New Hampshire Department of Environmental Services
www.google.com (n.d.) https://www.google.com/books/edition/The_Geology_of_the_Ammonoosuc_Mining_Dis/iV7PAAAAMAAJ?hl
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