Fort Baker

The Fort Baker is a manganese mine located in Humboldt 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: Fort Baker
Secondary: Porter Ranch

Commodity

Primary: Manganese
Tertiary: Chromium

Location

State: California
County: Humboldt

Land Status

Land ownership: National Forest
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

Not available

Ownership

Owner Name: Russ Inv. Co. (L. V. Smith, Secretary)

Production

Not available

Deposit

Record Type: Site
Operation Category: Producer
Operation Type: Unknown
Years of Production:
Organization:
Significant: N
Deposit Size: M

Physiography

General Physiographic Area: Pacific Mountain System
Physiographic Province: Pacific Border Province
Physiographic Section: California Coast Ranges

Mineral Deposit Model

Not available

Orebody

Not available

Structure

Not available

Alterations

Not available

Rocks

Name: Shale
Role: Host
Age Type: Host Rock
Age Young: Late Cretaceous

Analytical Data

Analytical Data: ORE GRADE OVER 30 PERCENT MANGANESE

Materials

Ore: Psilomelane

Comments

Comment (Location): LOCATED IN NW 1/4 SW 1/4 SECTION 32 , MINE SYMBOL

Comment (Production): IN 1918, 473 TONS OF ORE AVERAGING 47 PERCENT MANGANESE AND 13 PERCENT SILICA, WAS SHIPPED. MINE WAS WORKED UNTIL 1920 WHEN IT WAS ABANDONED WITH TOTAL PRODUCTION OF 654TONS. LITTLE ORE IN SIGHT IN 1942 BUT CHANCES OF FINDING ADDITIONAL HIGH-GRADE ORE ARE FAVORABLE. TOTAL PRODUCTION TO 1958 WAS MORE THAN 2000 TONS 45.2 -50.6% MN.

Comment (Workings): OPEN CUTS, SHALLOW SHAFTS AND TUNNELS.

Comment (Geology): ORE HOSTED IN FRANCISCAN COMPLEX--L. TO L. ; GEOL.DESC: CHERT BODY FOLDED INTO AN ANTICLINE PITCHING GENTLY NE AND FAULTED ALONG SE LIMB. A BRECCIATED ZONE ASSOCIATED WITH THE FAULT CONTAINED THE MAIN ORE BODIES. HIGH GRADE ORE IS PSILOMELANE OCCURING AS THIN SEEMS IN RED SHALE OF THE BRECCIATED ZONE.

References

Reference (Deposit): CDM BULL. 134, PT. 1, PL. 19

Reference (Deposit): D.O.M. BULL. 152, 1950, PP. 65-67

Reference (Deposit): CALIF. JOUR. MINES & GEOLOGY, V.37, NO. 4, OCT. 1941, PP. 518-19; ADD. REF.: USBM RI 5579, P. 7; PSFC FIG. 7, CALIF. DIV. MINES BULL. 179, FIG. 13; MR-23

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.