USGS Mineral Resources Data System
Type: Historical mine record
Supports:
- mine identity
- development status
- commodities
- underground eligibility evidence
California · Nevada County
Twin Sisters
Unconfirmed Gold Mixed Underground / Surface
Key facts
- State
- California
- County
- Nevada
- Mining district
- Alleghany
- Development status
- Past Producer
- Mine type
- Mixed underground / surface
- Primary commodity
- Gold
- Verification
- Unconfirmed
Mine Location
Approximate AreaDocumented underground workings
Mindat locality description
A former lode Au-As occurrence/mine located in sec. 12 & sec. 13, T18N, R10E, MDM, 1.1 km (0.7 mile) ENE of Snow Point (coordinates of record), S of the Middle Yuba River (2 miles S of Eureka), on National Forest land. MRDS database stated accuracy for…
Historical mapped workings
USGS historical topographic mapping. Features may no longer exist.
- 2 shaft symbols
- 1 adit symbol
View individual source records (2)
Every underlying record used to build the summary above, for research/verification use.
- USGS MRDS working type: Surface/Underground
- MRDS work_type documents underground workings: Surface/Underground · work_type
Verification
Unconfirmed
Source records support underground workings, but UndergroundMines has not yet independently verified this mine.
Why it's listed
Source records document both underground and surface mining.
History & operations
Historical record
- Development status: Past Producer
Commodities & minerals
Reported minerals
- Quartz
- Gold
- Native Gold
- Quartz
Access & recent conditions
- Land
- unknown
Community reports
No community field reports yet.
I Visited This MineSources & evidence
USGS Historical Topographic Mine Features
Type: Historical mapped physical features
Dataset: DOI 10.5066/P9TAALR6
Supports:
- mapped shaft symbols (2)
- mapped adit symbols (1)
Historical mapped features may no longer exist.
Mindat
Type: Mineralogical locality database
Record: Mindat Locality: 84826
Supports:
- locality identity
- reported minerals (2)
A Mindat locality match does not by itself establish underground workings.
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