| Deposit ID | 10107483 |
|---|---|
| MRDS ID | W701123 |
| Record type | Site |
| Current site name | Keystone Mine |
| Alternate or previous names | La Mina, La Esperanza, Juncos Mine |
| Related records | 10056940 |
| Geographic coordinates: | -65.89778, 18.23399 (WGS84) |
|---|---|
| Relative position | 2.5 KM EAST OF TOWN OF JUNCOS |
Political divisions (FIPS codes)
Juncos Municipio(county)
Puerto Rico(state)
United States(country)
North America(continent)
Land(continent)
USGS map quadrangles
Juncos(quadrangle 1:24,000 scale)
Puerto Rico(quadrangle 1:250,000 scale)
Hydrologic units (watersheds)
Eastern(hydrologic unit)
Puerto Rico(hydrologic accounting unit)
Puerto Rico(hydrologic subregion)
Caribbean(hydrologic region)
| Country | State |
|---|---|
| United States | Puerto Rico |
| Commodity | Importance |
|---|---|
| Iron | Primary |
| Copper | Primary |
| Materials | Type of material |
|---|---|
| Chalcopyrite | Ore |
| Cuprite | Ore |
| Goethite | Ore |
| Hematite | Ore |
| Magnetite | Ore |
| Malachite | Ore |
| Calcite | Gangue |
| Epidote | Gangue |
| Garnet | Gangue |
| Quartz | Gangue |
| Result | ASSAYS: 10.2-67.4% FE |
|---|---|
| Result | 3.7-12.6% SIO2 FOR ORE |
| Model code | 62 |
|---|---|
| USGS model code | 18d |
| Deposit model name | Skarn Fe |
| Host or associated | Associated | ||
|---|---|---|---|
| Rock type | Plutonic Rock > Mafic Intrusive Rock > Diorite | ||
| |||
| Host or associated | Host |
|---|---|
| Rock type | Metamorphic Rock > Metasedimentary Rock > Marble |
| (1) | -65.89778, 18.23399 |
|---|
| General form | TWO LENTICULAR LAYERS |
|---|---|
| Strike | N50W |
| Dip | 50-70 NE |
| Length | 500M |
| Width | 15M |
| Development status | Producer |
|---|---|
| Commodity type | Metallic |
| Deposit size | Small |
| Significant | No |
| Year of first production | 1951 |
| Year of last production | 1953 |
| Year | 1951 | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Material | ORE | ||||||||||||||
| Accuracy | Accurate | ||||||||||||||
| Description | Ap_Grade: ^>60% Fe | ||||||||||||||
| |||||||||||||||
| Year | 1952 | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Material | ORE | ||||||||||||||
| Accuracy | Accurate | ||||||||||||||
| Description | Ap_Grade: ^>60% Fe | ||||||||||||||
| |||||||||||||||
| Year | 1953 | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Period | 1951-53 | ||||||||||||||
| Material | ORE | ||||||||||||||
| Accuracy | Accurate | ||||||||||||||
| Description | Cp_Grade: ^>60 % Fe | ||||||||||||||
| |||||||||||||||
| Year | 1953 | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Material | ORE | ||||||||||||||
| Accuracy | Accurate | ||||||||||||||
| Description | Ap_Grade: ^>60% Fe | ||||||||||||||
| |||||||||||||||
| Agency | Database name | Acronym | Record ID | Notes |
|---|---|---|---|---|
| USGS | Mineral Resources Data System | MRDS | W701123 |
COX, DENNIS P., AND BRIGGS, REGINALD P., 1973, METALLOGENIC MAP OF PUERTO RICO: U.S. GEOLOGICAL SURVEY, MISCELLANEOUS GEOLOGIC INVESTIGATIONS MAP I-721, ACCOMPANIED BY EXPLANATORY PAMPHLET, 6 P.
VAZQUEZ, LEOVIGILDO, AND OWENS,JAMES P., 1958, GEOLOGY AND ORE DEPOSITS OF THE KEYSTONE IRON MINE NEAR JUNCOS, PUERTO RICO; ECONOMIC DEVELOPMENT ADMINISTRATION, DEPT. OF INDUSTRIAL RESEARCH, BULL.6,
VAZQUEZ, LEOVIGILDO, 1960, GEOLOGY AND ORE DEPOSITS OF THE KEYSTONE IRON MINE NEAR JUNCOS, PUERTO RICO, ECONOMIC DEVELOPMENT ADMINISTRATION, DEPT. OF INDUSTRIAL RESEARCH, BULL. NO. 7
BROEDEL, C. H., 1961, PRELIMINARY GEOLOGIC MAP SHOWING IRON AND COPPER PROSPECTS IN THE JUNCOS QUADRANGLE, PUERTO RICO: U. S. GEOLOGICAL SURVEY MISC. GEOL. INV. MAP I-326.
VAZQUEZ,L.,1960, GEOLOGY AND ORE DEPOSITS OF THE KEYSTONE IRON MINE, DEPT. OF INDUSTRIAL RESEARCH, BULL.7
| Subject category | Comment text |
|---|---|
| Deposit | TWO LENTICULAR LAYERS WHICH APPEAR TO BE CONTACT METAMORPHIC IN ORIGIN. ALL MAGNETITE OCCURS IN THIN TUFFACEOUS MARBLE. |
| Deposit | 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 |
| Type | Date | Name | Affiliation | Comment |
|---|---|---|---|---|
| Reporter | 01-JAN-1990 | Paidakovich, Matthew E. | U.S. Geological Survey | |
| Updater | 01-AUG-1991 | Paidakovich, Matthew E. | U.S. Geological Survey |
Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.