Plomosa Placers

The Plomosa Placers is a gold mine located in La Paz county, Arizona at an elevation of 1,499 feet.

About the MRDS Data:

All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.

Mine Info

Satelite View

MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.

Site Name

Primary: Plomosa Placers

Commodity

Primary: Gold
Tertiary: Platinum

Location

State: Arizona
County: La Paz
District: Southern Plomosa District

Land Status

Land ownership: BLM Administrative Area
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.

Holdings

Not available

Workings

Type: Surface/Underground

Ownership

Owner Name: Frank Magini
Home Office: Phoenix, Az.
Years: 1986 -

Production

Not available

Deposit

Record Type: Site
Operation Category: Past Producer
Deposit Type: Stream Placer
Operation Type: Unknown
Year First Production: 1865
Discovery Year: 1860
Years of Production:
Organization:
Significant: N
Deposit Size: L

Physiography

General Physiographic Area: Intermontane Plateaus
Physiographic Province: Basin And Range Province
Physiographic Section: Sonoran Desert

Mineral Deposit Model

Model Name: Placer Au-PGE

Orebody

Form: PROBABLY POCKETS AND BARS

Structure

Not available

Alterations

Not available

Rocks

Name: Schist
Role: Associated
Age Type: Host Rock
Age Young: Pliocene

Analytical Data

Not available

Materials

Ore: Gold

Comments

Comment (Location): LOCATION GIVEN IS ON PLACER TAILINGS IN S/2 SEC. 4. GOLD-BEARING GRAVELS ARE FOUND FOR ABOUT 3-4 MI ALONG THE WEST EDGE OF THE PLOMOSA MOUNTAINS IN AND NEAR PLOMOSA WASH.

Comment (Production): ESTIMATES OF AVERAGE VALUE OF GOLD RANGE FROM $0.71-1.77/CY. PRODUCTION RECORDS NOT AVAILABLE FROM 1860 TO 1900

Comment (Development): PREVIOUS OPERATORS INCLUDE YUMA CONSOLIDATED CO., PLOMOSA PLACER CO. LARGE-SCALE DRYWASHING UNSUCCESSFUL IN 1910'S.

Comment (Deposit): GOLD WAS FOUND IN SEVERAL HORIZONS IN THE GRAVEL; CEMENTED GRAVELS WERE ESPECIALLY RICH.

Comment (Workings): IN SOME LOCALITIES PITS HAVE BEEN SUNK TO DEPTHS OF 20 TO >50 FT TO BEDS OF CEMENT WHICH ARE RICHER THAN THE GRAVEL.

Comment (Commodity): UNVERIFIED REPORT OF PGE

Comment (Geology): THE SCHIST, WHICH CONTAINS GOLD-BEARING QUARTZ VEINS AND STRINGERS, IS MOST LIKELY SOURCE OF AU

References

Reference (Deposit): BUTLER, G.M., 1937, ARIZONA GOLD PLACERS AND PLACERING (4TH ED.): ARIZONA BUREAU OF MINES BULLETIN 142, P. 29-30.

Reference (Deposit): ELSING, M.J., AND HEINEMAN, R.E.S., 1936, ARIZONA METAL PRODUCTION: ARIZONA BUREAU OF MINES BULLETIN 140, P. 104.

Reference (Deposit): JOHNSON, M.G., 1972, PLACER GOLD DEPOSITS OF ARIZONA: U.S. GEOLOGICAL SURVEY BULLETIN 1355, P. 80-81.

Reference (Deposit): WILSON, E.D., 1961, GOLD PLACERS AND PLACERING IN ARIZONA: ARIZONA BUREAU OF MINES BULLETIN 168, P. 29.

Reference (Deposit): QUIRING, HEINRICH, 1962, PLATINMETALLE IN DIE METALLISCHEN ROHSTOFFE 16 BAND: STUTTGART, FERDINAND ENKE VERLAG, P. 245.

Reference (Deposit): ORRIS, G.J., AND BLISS, J.D., 1985, GEOLOGIC AND GRADE-VOLUME DATA ON 330 GOLD PLACER DEPOSITS: U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 85-213, 172 P.

Reference (Deposit): NIEMUTH, N.J., 1987, ARIZONA MINERAL DEVELOPMENT 1984-1986: ARIZONA DEPARTMENT OF MINES AND MINERAL RESOURCES DIRECTORY 29, 46 P.

Reference (Other Database): CIMRI

Reference (Production): WILSON, 1961

Reference (Reserve-Resource): ORRIS AND BLISS, 1985

Arizona Gold

"Where to Find Gold in Arizona" looks at the density of modern placer mining claims along with historical gold mining locations and mining district descriptions to determine areas of high gold discovery potential in Arizona. Read more: Where to Find Gold in Arizona.