Dufrene

The Dufrene is a mine located in Amador county, California.

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: Dufrene

Commodity

Tertiary: Manganese

Location

State: California
County: Amador

Land Status

Not available

Holdings

Not available

Workings

Not available

Ownership

Owner Name: Fred Dufrene

Production

Not available

Deposit

Record Type: Site
Operation Category: Prospect
Operation Type: Unknown
Years of Production:
Organization:
Significant: N

Physiography

General Physiographic Area: Pacific Mountain System
Physiographic Province: Cascade-Sierra Mountains
Physiographic Section: Sierra Nevada

Mineral Deposit Model

Not available

Orebody

Not available

Structure

Not available

Alterations

Not available

Rocks

Not available

Analytical Data

Not available

Materials

Ore: Rhodonite
Ore: Psilomelane
Ore: Pyrolusite
Gangue: Magnetite

Comments

Comment (Production): THE BEST EXPOSURE OF MANGANESE OXIDES IS IN THE SOUTHERN MOST CUT WHERE THE CENTER OF THE METACHERT IS MOSTLY OF OXIDES, CHIEFLY HARD BLUE-BLACK PSILOMELANE; THIS BED PROBABLY CONTAINS 45 PERCENT MANGANESE. SOME OF THE BLACK OXIDE ORE IS GOOD GRADE BUT THE AMOUNT AVAILABLE IS SMALL

Comment (Workings): SMALL SHAFT AND A SERIES OF OPEN CUTS

Comment (Location): LOCATED IN SW 1/4 SECTION 27

Comment (Geology): GEOL.DESC: ORE LIES IN BED OF MANGANIFEROUS META-CHERT 5 TO 8 FT. THICK; STRIKING N 5 - 15 W; DIPPING 65 - 75 E. THE METACHERT IS ENCLOSED IN METAVOLCANICS (IN PAST GREENSTONE) AND META-TUFFS. THE FORMATION IS THOUGHT TO BE THE AMADOR GROUP. THE META-CHERT IS MASSIVE AND THICK BEDDED; IN PART CHALCEDONIC TO OPALINE; IN PART CRYSTALLIZED TO FINE GRAINED QUARTZITE. MANGANESE OXIDES OCCUR AS BANDS, CRUSTS, AND POCKETS IN THE METACHERT. AMOUNT OF OXIDE PRESENT SMALL AND SMALL AMOUNT OF RHODONITE IS PRESENT. OXIDE WHERE IDENTIFIED IS HARD, BLUE BLACK PSILOMELANE. AT SOME PLACES META-CHERT IS CUT BY BANDS OR VEINLETS 1/2 TO 1 IN. WIDE OF MAGNETITE

References

Reference (Deposit): CALIF. JOUR. MINES & GEOL. V. 50, NO. 1, JAN. 1954, P.268, PL. 1

Reference (Deposit): DOM BULL. 152, P.28

California Gold

"Where to Find Gold in California" 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 California. Read more: Where to Find Gold in California.