Little Johnnie Mine

Occurrence in Gunnison county in Colorado, United States with commodities Thorium, REE

Sections on this page

Identification information
Geographic coordinates
Site location context
Geographic areas
Public Land Survey System information
Commodities
Materials information
Host and associated rocks
Nearby scientific data
Geologic structures
Ore body information
Controls for ore emplacement
Economic information about the deposit and operations
Mining district
Land status
Ownership information
Links to other databases
Bibliographic references
General comments
Reporter information

Geologic information

Identification information

Deposit ID	10014417
MRDS ID	D011172
Record type	Site
Current site name	Little Johnnie Mine
Alternate or previous names	Unpatented Claims: Little Johnnie Nos. 1-2, Little Johnnie Extension, Cathey Nos. 1-5, Charley Nos. 1-5

Geographic coordinates

Geographic coordinates:	-107.08674, 38.32167 (WGS84)
Elevation	2719
Relative position	17.4 MILES S 31 W FROM GUNNISON

Site location context

Political divisions (FIPS codes)

Gunnison(county)

Colorado(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Powderhorn(quadrangle 1:24,000 scale)

Montrose(quadrangle 1:100,000 scale)

Montrose(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Upper Gunnison(hydrologic unit)

Gunnison(hydrologic accounting unit)

Gunnison(hydrologic subregion)

Upper Colorado(hydrologic region)

Federal lands

Bureau of Land Management(Bureau of Land Management CO)

Bureau of Land Management CO BLM(Type of land area)

BLM(Federal land areas administered by BLM)

Geographic areas

Country	State	County
United States	Colorado	Gunnison

Public Land Survey System information

Meridian	Township	Range	Section	Fraction	State
New Mexico	047N	002W	15	SE OF SW	Colorado

Comments on the location information

ON NORTH SIDE OF MILKRANCH GULCH DRAINAGE BASIN AND EAST OF OLD LOT MINE. ; INFO FROM LAND.ST :1976

Commodities

Commodity	Importance
Thorium	Primary
REE Critical	Tertiary

Materials information

Materials	Type of material
Thorite	Ore
Allophane	Gangue
Apatite	Gangue
Barite	Gangue
Chlorite	Gangue
Clinozoisite	Gangue
Goethite	Gangue
Hematite	Gangue
Quartz	Gangue
Rutile	Gangue
Tourmaline	Gangue
Xenotime	Gangue

Analytical data

Result	ADAMS AND MOORE (1951) GIVE CHEMICAL ANALYSIS OF VEIN MATERIAL AS 2.29% TH02 AND 0.50% RARE-EARTH OXIDE. RADIOMETRIC ANALYSES TABULATED BY OLSON AND WALLACE (1956) (EACH SET OF VALUES IS % EQUIV URANIUM AND CALCULATED % TH02 ASSUMING THAT ALL RADIOACTIVITY IS DUE TO TH): 0.13, 0.73
Result	0.045, 0.25
Result	0.12, 0.67
Result	0.11, 0.61
Result	0.88, 4.9
Result	0.019, 0.10
Result	0.034, 0.19
Result	0.20, 1.12
Result	0.031, 0.17
Result	0.15, 0.84
Result	0.009, 0.05
Result	0.014, 0.08

Host and associated rocks

Host or associated

Associated

Rock type

Plutonic Rock > Granitoid > Syenite

Rock unit name

Thorium Vein;Syenite;Gabbro;Diabase Dikes

Rock description

Thorium Vein;Syenite;Gabbro;Diabase Dikes

Stratigraphic age (youngest)	Late Ordovician
Stratigraphic age (youngest)	Neoproterozoic

Host or associated Associated

Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite > Diabase
Host or associated Associated

Rock type Plutonic Rock > Mafic Intrusive Rock > Gabbro
Host or associated Host

Rock type Metamorphic Rock > Metasedimentary Rock > Quartzite

Host or associated	Associated
Rock type	Plutonic Rock > Mafic Intrusive Rock > Diorite > Diabase

Host or associated	Associated
Rock type	Plutonic Rock > Mafic Intrusive Rock > Gabbro

Host or associated	Host
Rock type	Metamorphic Rock > Schist
Rock unit name	Dubois Greenstone--Felsite And Felsite Porphyry;Dubois Greenstone--Hornblende Schist And Amphibolite
Rock description	Dubois Greenstone--Felsite And Felsite Porphyry;Dubois Greenstone--Hornblende Schist And Amphibolite

Host or associated Host

Rock type Metamorphic Rock > Amphibolite

Nearby scientific data

(1)	-107.08674, 38.32167	ListMap

Economic information

Geologic structures

Type of structure	Regional
Structure description	Gunnison Uplift, San Juan Volcanic Field
Type of structure	Local
Structure description	Gunnison Gold Belt, Iron Hill Alkalic Complex, Tolvar Peak Stock

Ore body information

General form TABULAR

Thickness 1.52M

General form	TABULAR
Thickness	1.52M

Controls for ore emplacement

Ne-Trending Vein Cutting Greenstone

Economic information about the deposit and operations

Development status	Occurrence
Commodity type	Metallic
Deposit size	Small
Significant	No
Discovery year	1949
Discoverer	Neil Foreman And J.A. Mcgregor

Mining district

District name	Goose Creek District

Land status

Ownership category	BLM Administrative Area

Ownership information

Type Owner-Operator

Owner John A. Mcgregor

Home office Powderhorn

First year 1962

Type	Owner-Operator
Owner	John A. Mcgregor
Home office	Powderhorn
First year	1962

Comments on the workings information

40-FT LITTLE JOHNNIE NO. 1 TUNNEL; 389-FT LITTLE JOHNNIE NO. 2 TUNNEL; SMALL PROSPECT SHAFT; SURFACE CUTS.

Reference information

Links to other databases

Agency	Database name	Acronym	Record ID	Notes
USGS	Mineral Resources Data System	MRDS	D011172

Bibliographic references

Deposit

HEDLUND, D.C., AND OLSON, J.C., 1975, GEOLOGIC MAP OF THE POWDERHORN QUADRANGLE, GUNNISON AND SAGUACHE COUNTIES, COLORADO: USGS MAP GQ-1178.
Deposit

HEDLUND, D.C., AND OLSON, J.C., 1961, FOUR ENVIRONMENTS OF THORIUM-, NIOBIUM-, AND RARE-EARTH-BEARING MINERALS IN THE POWDERHORN DISTRICT OF SOUTHWESTERN COLORADO: USGS PROF. PAPER 424-B, P. B283-B286.
Deposit

OLSON, J.C., AND HEDLUND, D.C., 1981, ALKALIC ROCKS AND RESOURCES OF THORIUM AND ASSOCIATED ELEMENTS IN THE POWDERHORN DISTRICT, GUNNISON COUNTY, COLORADO: USGS PROF. PAPER 1049-C.
Deposit

OLSON, J.C., AND WALLACE, S.R., 1956, THORIUM AND RARE-EARTH MINERALS IN POWDERHORN DISTRICT, GUNNISON COUNTY, COLORADO: USGS BULL. 1027-0.
Deposit

NELSON-MOORE, J.L., AND OTHERS, 1978, RADIOACTIVE MINERAL OCCURRENCES OF COLORADO AND BIBLIOGRAPHY: CGS BULL. 40, P. 175.
Deposit

ADAMS, J.W., AND MOORE, F.B., 1951, AEC PRELIM. RECON. REPT. RR-95.
Deposit

COLORADO DIV. MINES INF. REPTS.

General comments

Subject category	Comment text
Deposit	THORIUM VEINS IN THIS AREA ARE ONE OF FOUR ENVIRONMENTS OF TH OCCURRENCE KNOWN IN POWDERHORN-IRON HILL AREA AND ARE PROBABLY RELATED TO EMPLACEMENT OF LATE PRECAMBRIAN SYENITES NORTH AND WEST OF IRON HILL AND OF YOUNGER LATE PRECAMBRIAN OR CAMBRIAN CARBONATITES AT IRON HILL. FOLIATION OF DUBOIS GREENSTONE FELSITE AND SEVERAL LAYERS OF HORNBLENDE SCHIST AND AMPHIBOLITE COUNTRY ROCK TREND GENERALLY N 55 TO 60 E, 80 TO 90 NW. OLSON AND WALLACE (1956) DESCRIBE SEQUENCE AS QUARTZ-BIOTITE SCHIST AND QUARTZITE, METARHYOLITE PORPHYRY, AMPHIBOLITE DIKES AND BODIES ALL CUT BY SMALL FAULTS, BY SYENITE DIKES AND LARGE NW-TRENDING GABBRO DIKE, AND BY QUARTZ, CARBONATE, SODA-AMPHIBOLE, AND BRECCIA VEINS. POORLY EXPOSED VEIN IS MINERALIZED FAULT TRENDING N 65 E, DIPPING WITHIN 10 DEG OF VERTICAL. VEIN RANGES FROM UNDER 6 INCHES TO 5 FT WIDE, WITH AVERAGE NOT EXCEEDING 2 FT. VEIN MAY EXTEND FARTHER NE REAPPEARING AS TRACHYTE PORPHYRY DIKE BUT IS SEPARATED FROM IT BY TWO NW-TRENDING CAMBRO-ORDOVICIAN
Deposit	DIABASE DIKES. MINERALOGY CHARACTERIZED BY SUBHEDRAL TO ANHEDRAL MASSES OF THORITE OR THOROGUMMITE, EUHEDRAL CRYSTALS OF HEMATITE PARTLY ALTERED TO GOETHITE, COARSE-GRAINED BARITE, AND POSSIBLE ACCESSORY XENOTIME (Y RARE EARTH).

Subject category

Comment text

Deposit

THORIUM VEINS IN THIS AREA ARE ONE OF FOUR ENVIRONMENTS OF TH OCCURRENCE KNOWN IN POWDERHORN-IRON HILL AREA AND ARE PROBABLY RELATED TO EMPLACEMENT OF LATE PRECAMBRIAN SYENITES NORTH AND WEST OF IRON HILL AND OF YOUNGER LATE PRECAMBRIAN OR CAMBRIAN CARBONATITES AT IRON HILL. FOLIATION OF DUBOIS GREENSTONE FELSITE AND SEVERAL LAYERS OF HORNBLENDE SCHIST AND AMPHIBOLITE COUNTRY ROCK TREND GENERALLY N 55 TO 60 E, 80 TO 90 NW. OLSON AND WALLACE (1956) DESCRIBE SEQUENCE AS QUARTZ-BIOTITE SCHIST AND QUARTZITE, METARHYOLITE PORPHYRY, AMPHIBOLITE DIKES AND BODIES ALL CUT BY SMALL FAULTS, BY SYENITE DIKES AND LARGE NW-TRENDING GABBRO DIKE, AND BY QUARTZ, CARBONATE, SODA-AMPHIBOLE, AND BRECCIA VEINS. POORLY EXPOSED VEIN IS MINERALIZED FAULT TRENDING N 65 E, DIPPING WITHIN 10 DEG OF VERTICAL. VEIN RANGES FROM UNDER 6 INCHES TO 5 FT WIDE, WITH AVERAGE NOT EXCEEDING 2 FT. VEIN MAY EXTEND FARTHER NE REAPPEARING AS TRACHYTE PORPHYRY DIKE BUT IS SEPARATED FROM IT BY TWO NW-TRENDING CAMBRO-ORDOVICIAN

Deposit

DIABASE DIKES. MINERALOGY CHARACTERIZED BY SUBHEDRAL TO ANHEDRAL MASSES OF THORITE OR THOROGUMMITE, EUHEDRAL CRYSTALS OF HEMATITE PARTLY ALTERED TO GOETHITE, COARSE-GRAINED BARITE, AND POSSIBLE ACCESSORY XENOTIME (Y RARE EARTH).

Reporter information

Type	Date	Name	Affiliation	Comment
Reporter	01-JAN-1984	Schwochow, Stephen D.	Colorado Geological Survey

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Maps centered on this site

Authoritative Colorado resources

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