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Keystone Mine, Juncos, Puerto Rico, USAi
| Regional Level Types | |
|---|---|
| Keystone Mine | Mine |
| Juncos | Municipality |
| Puerto Rico | Unincorporated Territory |
| USA | Country |
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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:
| Place | Population | Distance |
|---|---|---|
| El Mangó | 1,979 (2015) | 2.0km |
| Juncos | 8,905 (2015) | 2.5km |
| Pueblito del Rio | 1,481 (2015) | 3.8km |
| Lomas | 953 (2015) | 4.1km |
| Benitez | 1,334 (2015) | 4.9km |
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 ElementsCommodity 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 DiagramDetailed 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 | |||
|---|---|---|---|
| ⓘ | Chalcopyrite | 2.CB.10a | CuFeS2 |
| ⓘ | Pyrite | 2.EB.05a | FeS2 |
| Group 4 - Oxides and Hydroxides | |||
| ⓘ | Goethite ? | 4.00. | Fe3+O(OH) |
| ⓘ | Cuprite | 4.AA.10 | Cu2O |
| ⓘ | Magnetite | 4.BB.05 | Fe2+Fe3+2O4 |
| ⓘ | Hematite | 4.CB.05 | Fe2O3 |
| ⓘ | Quartz | 4.DA.05 | SiO2 |
| Group 5 - Nitrates and Carbonates | |||
| ⓘ | Calcite | 5.AB.05 | CaCO3 |
| ⓘ | Azurite | 5.BA.05 | Cu3(CO3)2(OH)2 |
| ⓘ | Malachite | 5.BA.10 | Cu2(CO3)(OH)2 |
| Group 9 - Silicates | |||
| ⓘ | Epidote | 9.BG.05a | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| ⓘ | Chrysocolla | 9.ED.20 | Cu2-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
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Azurite | Cu3(CO3)2(OH)2 |
| H | ⓘ Chrysocolla | Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1 |
| H | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| H | ⓘ Goethite | Fe3+O(OH) |
| H | ⓘ Malachite | Cu2(CO3)(OH)2 |
| H | ⓘ Serpentine Subgroup | D3[Si2O5](OH)4 |
| C | Carbon | |
| C | ⓘ Azurite | Cu3(CO3)2(OH)2 |
| C | ⓘ Calcite | CaCO3 |
| C | ⓘ Malachite | Cu2(CO3)(OH)2 |
| O | Oxygen | |
| O | ⓘ Azurite | Cu3(CO3)2(OH)2 |
| O | ⓘ Calcite | CaCO3 |
| O | ⓘ Chrysocolla | Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1 |
| O | ⓘ Cuprite | Cu2O |
| O | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| O | ⓘ Goethite | Fe3+O(OH) |
| O | ⓘ Hematite | Fe2O3 |
| O | ⓘ Magnetite | Fe2+Fe23+O4 |
| O | ⓘ Malachite | Cu2(CO3)(OH)2 |
| O | ⓘ Quartz | SiO2 |
| O | ⓘ Garnet Group | X3Z2(SiO4)3 |
| O | ⓘ Serpentine Subgroup | D3[Si2O5](OH)4 |
| Al | Aluminium | |
| Al | ⓘ Chrysocolla | Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1 |
| Al | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Si | Silicon | |
| Si | ⓘ Chrysocolla | Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1 |
| Si | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Si | ⓘ Quartz | SiO2 |
| Si | ⓘ Garnet Group | X3Z2(SiO4)3 |
| Si | ⓘ Serpentine Subgroup | D3[Si2O5](OH)4 |
| S | Sulfur | |
| S | ⓘ Chalcopyrite | CuFeS2 |
| S | ⓘ Pyrite | FeS2 |
| Ca | Calcium | |
| Ca | ⓘ Calcite | CaCO3 |
| Ca | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Fe | Iron | |
| Fe | ⓘ Chalcopyrite | CuFeS2 |
| Fe | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Fe | ⓘ Goethite | Fe3+O(OH) |
| Fe | ⓘ Hematite | Fe2O3 |
| Fe | ⓘ Magnetite | Fe2+Fe23+O4 |
| Fe | ⓘ Pyrite | FeS2 |
| Cu | Copper | |
| Cu | ⓘ Azurite | Cu3(CO3)2(OH)2 |
| Cu | ⓘ Chalcopyrite | CuFeS2 |
| Cu | ⓘ Chrysocolla | Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1 |
| Cu | ⓘ Cuprite | Cu2O |
| Cu | ⓘ Malachite | Cu2(CO3)(OH)2 |
Other Databases
| Link to USGS MRDS: | 10107483 |
|---|
Other Regions, Features and Areas containing this locality
Caribbean PlateTectonic Plate
North America
- Central AmericaSubregion
North America Plate
- Greater Antilles ArcVolcanic Arc
The CaribbeanRegion
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Keystone Mine, Juncos, Puerto Rico, USA