Past ProducerManganese, SilicaSurface-UndergroundUSGS MRDS
Location
State
California
County
San Luis Obispo
Coordinates
35.26577, -120.76427
Commodities
Tertiary
Manganese, Silica
Mine Details
Status
Past Producer
Type
Surface-Underground
First Production
1917
Discovery Year
1916
Data Source
USGS MRDS
Source ID
10213583
What This Means
This mine is a past producer — it was once operational but is no longer actively mining. Past producer sites may still have environmental impacts including disturbed land, tailings piles, and potential water quality effects. Some past producer sites have been reclaimed, while others remain as-is. Check with your state mining or environmental agency for current site conditions.