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Keystone Mine, Juncos, Puerto Rico, USAi
Regional Level Types
Keystone MineMine
JuncosMunicipality
Puerto RicoUnincorporated Territory
USACountry

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Latitude & Longitude (WGS84):
18° 13' 59'' North , 65° 53' 53'' West
Latitude & Longitude (decimal):
Type:
Deposit first discovered:
Before 1951
Köppen climate type:
Nearest Settlements:
PlacePopulationDistance
El Mangó1,979 (2015)2.0km
Juncos8,905 (2015)2.5km
Pueblito del Rio1,481 (2015)3.8km
Lomas953 (2015)4.1km
Benitez1,334 (2015)4.9km
Mindat Locality ID:
25586
Long-form identifier:
mindat:1:2:25586:1
GUID (UUID V4):
0
Other/historical names associated with this locality:
La Mina; La Esperanza; Juncos Mine; Keystone Iron Mine


Iron mine mined between 1951 and 1953 from open pit
Deposit: Two lenticular layers which appear to be contact metamorphic in origin. All magnetite occurs in thin tuffaceous marble. Believed to be the largest deposit of iron ore in puerto rico (broedel, 1961). [previous updater and date: bawiec, walter j., 90 07.] ; info.src : 1 pub lit; 2 unpub rept

Deposit type: Skarn Fe

Development: Mine

Ore(s): Contact Metamorphic In Tuffaceous Marble


Production From Keystone And Island Queen Mine Totaled 220,475 Tons Of Ore With 60% Fe.
Model: 18d Skarn Fe

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


12 valid minerals.

Rock Types Recorded


Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Azurite
Formula: Cu3(CO3)2(OH)2
ⓘ Calcite
Formula: CaCO3
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ Chrysocolla
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
ⓘ Cuprite
Formula: Cu2O
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
ⓘ Goethite ?
Formula: Fe3+O(OH)
ⓘ Hematite
Formula: Fe2O3
ⓘ 'Limonite'
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Malachite
Formula: Cu2(CO3)(OH)2
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘGoethite ?4.00.Fe3+O(OH)
ⓘCuprite4.AA.10Cu2O
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘHematite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘAzurite5.BA.05Cu3(CO3)2(OH)2
ⓘMalachite5.BA.10Cu2(CO3)(OH)2
Group 9 - Silicates
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘChrysocolla9.ED.20Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Unclassified
ⓘ'Limonite'-
ⓘ'Garnet Group'-X3Z2(SiO4)3
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4

List of minerals for each chemical element

HHydrogen
Hⓘ AzuriteCu3(CO3)2(OH)2
Hⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Hⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ GoethiteFe3+O(OH)
Hⓘ MalachiteCu2(CO3)(OH)2
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
CCarbon
Cⓘ AzuriteCu3(CO3)2(OH)2
Cⓘ CalciteCaCO3
Cⓘ MalachiteCu2(CO3)(OH)2
OOxygen
Oⓘ AzuriteCu3(CO3)2(OH)2
Oⓘ CalciteCaCO3
Oⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Oⓘ CupriteCu2O
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ GoethiteFe3+O(OH)
Oⓘ HematiteFe2O3
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MalachiteCu2(CO3)(OH)2
Oⓘ QuartzSiO2
Oⓘ Garnet GroupX3Z2(SiO4)3
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
AlAluminium
Alⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
SiSilicon
Siⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ QuartzSiO2
Siⓘ Garnet GroupX3Z2(SiO4)3
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
SSulfur
Sⓘ ChalcopyriteCuFeS2
Sⓘ PyriteFeS2
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
FeIron
Feⓘ ChalcopyriteCuFeS2
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ GoethiteFe3+O(OH)
Feⓘ HematiteFe2O3
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2
CuCopper
Cuⓘ AzuriteCu3(CO3)2(OH)2
Cuⓘ ChalcopyriteCuFeS2
Cuⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Cuⓘ CupriteCu2O
Cuⓘ MalachiteCu2(CO3)(OH)2

Other Databases

Link to USGS MRDS:10107483

Other Regions, Features and Areas containing this locality

Caribbean PlateTectonic Plate
North America
North America Plate

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