Alma | UndergroundMines

Key facts

State: California
County: Alameda
Development status: Past Producer
Mine type: Underground
Primary commodity: Copper
Verification: Unconfirmed

Mine Location

Approximate Area

Documented underground workings

Mindat locality description

A S-pyrite-Cu-Ag occurrence/mine located in sec. 34, T1S, R3W, MDM, 0.5 km (0.3 mile) NE of Leona Heights proper and 8.5 km (5.3 miles) E of Oakland center, on private land. Discovered prior to 1892. Owned by Leota C. Reed (1950). MRDS database accurac…

View full locality record on Mindat

View individual source records (2)

Every underlying record used to build the summary above, for research/verification use.

USGS MRDS working type: Underground

MRDS work_type documents underground workings: Underground · work_type

Verification

Unconfirmed

Source records support underground workings, but UndergroundMines has not yet independently verified this mine.

Verify Mine Flag Mine

Why it's listed

USGS source data documents underground workings for this record.

View sources & evidence

History & operations

Historical record

Development status: Past Producer

Commodities & minerals

Reported minerals

Bornite
Chalcocite
Chalcopyrite
Pyrite
Sphalerite
Alunogen
Boothite
Chalcanthite

View all 26 reported minerals

Bornite
Chalcocite
Chalcopyrite
Pyrite
Sphalerite
Alunogen
Boothite
Chalcanthite
Chalcopyrite
commodity:Copper
commodity:Gold
commodity:Iron pyrite
commodity:Silver
Copiapite
Copper-bearing Melanterite
Epsomite
Halotrichite
Hematite
Hexahydrite
Kröhnkite
Limonite
Melanterite
Native Copper
Pentahydrite
Pyrite
Römerite

Access & recent conditions

Land: unknown

Community reports

No community field reports yet.

I Visited This Mine

Sources & evidence

USGS Mineral Resources Data System

Type: Historical mine record

Supports:

mine identity
development status
commodities
underground eligibility evidence

Mindat

Type: Mineralogical locality database

Record: Mindat Locality: 3427

Supports:

locality identity
reported minerals (21)

A Mindat locality match does not by itself establish underground workings.

View on Mindat

Related underground mines

Leona Heights

California · Alameda County

Unconfirmed Copper Past Producer Underground

Historical mapped workings available