USGS Mineral Resources Data System
Type: Historical mine record
Supports:
- mine identity
- development status
- commodities
- underground eligibility evidence
California · Mariposa County
Porphyry Hill
Unconfirmed Gold Underground
Key facts
- State
- California
- County
- Mariposa
- Development status
- Past Producer
- Mine type
- Underground
- Primary commodity
- Gold
- Verification
- Unconfirmed
Mine Location
Approximate AreaDocumented underground workings
Mindat locality description
A former lode Au mine located in sec. 20, T5S, R18E, MDM, 3.6 km (2.2 miles) SSE of Mount Bullion and 5.1 km (3.2 miles) WSW of Mariposa, on the SW flank of Negro Hill (close to Agua Fria Creek). Operated in 1901, 1905 & 1907-1910. MRDS database stated…
View individual source records (2)
Every underlying record used to build the summary above, for research/verification use.
- Derived from MRDS oper_type (existing operation): Underground
- MRDS oper_type documents existing underground operation (dev_stat=Past Producer): Underground · oper_type
Verification
Unconfirmed
Source records support underground workings, but UndergroundMines has not yet independently verified this mine.
Why it's listed
USGS source data documents underground workings for this record.
History & operations
Historical record
- Development status: Past Producer
Commodities & minerals
Reported minerals
- Porphyry
Access & recent conditions
- Land
- unknown
Community reports
No community field reports yet.
I Visited This MineSources & evidence
Mindat
Type: Mineralogical locality database
Record: Mindat Locality: 82445
Supports:
- locality identity
- reported minerals (1)
A Mindat locality match does not by itself establish underground workings.
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