| Deposit ID | 10013761 |
|---|---|
| MRDS ID | D010225 |
| Record type | Site |
| Current site name | Ajax Mica Mine |
| Alternate or previous names | Floyd Hill Mica Mine |
| Related records | 10165743 |
| Geographic coordinates: | -105.44087, 39.74916 (WGS84) |
|---|---|
| Elevation | 2256 |
| Relative position | 10.3 MILES S 86 W FROM GOLDEN |
Political divisions (FIPS codes)
Clear Creek(county)
Colorado(state)
United States(country)
North America(continent)
Land(continent)
USGS map quadrangles
Saddleback Mountain(quadrangle 1:24,000 scale)
Denver West(quadrangle 1:100,000 scale)
Denver(quadrangle 1:250,000 scale)
Hydrologic units (watersheds)
Clear(hydrologic unit)
South Platte(hydrologic accounting unit)
South Platte(hydrologic subregion)
Missouri(hydrologic region)
| Country | State | County |
|---|---|---|
| United States | Colorado | Clear Creek |
| Meridian | Township | Range | Section | Fraction | State |
|---|---|---|---|---|---|
| 6th Principal | 003S | 072W | 34 | SW OF NW | Colorado |
| Commodity | Importance |
|---|---|
| Mica | Primary |
| Beryllium Critical | Tertiary |
| Materials | Type of material |
|---|---|
| Beryl | Ore |
| Muscovite | Ore |
| Albite | Gangue |
| Biotite | Gangue |
| Quartz | Gangue |
| Sericite | Gangue |
| Tourmaline | Gangue |
| Host or associated | Associated | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Rock type | Plutonic Rock > Pegmatite | ||||||||
| Rock unit name | Pegmatite | ||||||||
| Rock description | Pegmatite | ||||||||
| |||||||||
| Host or associated | Host |
|---|---|
| Rock type | Metamorphic Rock > Schist |
| Host or associated | Host |
|---|---|
| Rock type | Metamorphic Rock > Gneiss |
| Rock unit name | Idaho Springs Formation---Biotite Gneiss |
| Rock description | Idaho Springs Formation---Biotite Gneiss |
| (1) | -105.44087, 39.74916 |
|---|
| Type of structure | Regional |
|---|---|
| Structure description | Front Range Uplift, Denver Basin |
| Type of structure | Local |
| Structure description | Floyd Hill Fault Zone |
| General form | LENTICULAR, POD |
|---|---|
| Thickness | 4.88M |
| Length | 53.34M |
| Development status | Past Producer |
|---|---|
| Commodity type | Both |
| Deposit size | Small |
| Significant | No |
| Discovery year | 1875 |
| Year of first production | 1895 |
| Year of last production | 1944 |
| District name | Clear Creek Pegmatite Province |
|---|
| Ownership category | Private |
|---|
| Type | Owner |
|---|---|
| Owner | Ralph D. Naslund And Geroge Baer |
| First year | 1944 |
| Agency | Database name | Acronym | Record ID | Notes |
|---|---|---|---|---|
| USGS | Mineral Resources Data System | MRDS | D010225 | |
| U.S. Bureau of Mines | Minerals Availability System | MAS | 0080190090 |
SHERIDAN, D.M., AND MARSH, S.P., 1976, GEOLOGIC MAP OF THE SQUAW PASS QUADRANGLE, CLEAR CREEK, JEFFERSON, AND GILPIN COUNTIES, COLORADO: USGS MAP GQ-1337
| Subject category | Comment text |
|---|---|
| Deposit | Discovery Year: LATE 1800S |
| Deposit | ZONED PEGMATITE TRENDS GENERALLY EAST-WEST AND DIPS 30 S, CUTTING ACROSS GNEISSIC BEDDING AND SCHISTOSITY. DIKE IS CUT BY ROTATIONAL FAULT TRENDING N39 W, 75 NE. QUARTZ CORE WITH MINOR ALBITE AND MUSCOVITE IS ENCLOSED BY ALBITE-MUSCOVITE PEGMATITE. FOOTWALL OF DIKE CONTAINS CONCENTRATION OF SHEET MICA. |
| Type | Date | Name | Affiliation | Comment |
|---|---|---|---|---|
| Reporter | 01-FEB-1983 | Schwochow, Stephen D. | Colorado Geological Survey |
Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.
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