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Opal from
The Geysers, West Mayacmas Mining District, Sonoma County, California, USA


Locality type:Geothermal Field
Classification
Species:Opal
Formula:SiO2 · nH2O
Comments:Occurs as crusts of delicate capillary fibers.
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Opal data
Locality Data:Click here to view The Geysers, West Mayacmas Mining District, Sonoma County, California, USA
Data Identifiers
Mindat Occurrence Record ID:8260
Long-form Identifier:1:3:8260:0
GUID (UUID V4):0
Nearest other occurrences of Opal
5.8km (3.6 miles) ⓘSocrates Mine, Castle Rock Springs area, West Mayacmas Mining District, Sonoma County, California, USA
10.2km (6.3 miles) ⓘJumbo Mine (B & M Mine; Double Star Mine), Castle Rock Springs area, West Mayacmas Mining District, Sonoma County, California, USA
11.2km (7.0 miles) ⓘHelen Mine (Helen Mine group; Dead Broke Mine; American Mine), Castle Rock Springs, East Mayacmas Mining District, Lake County, California, USA
13.7km (8.5 miles) ⓘLivermore Quicksilver Mine, Cloverdale, West Mayacmas Mining District, Sonoma County, California, USA
17.1km (10.6 miles) ⓘGreat Western Mine (Laguna Western; Black Bart Mine; Tucker lease), Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA
21.8km (13.5 miles) ⓘPlymouth Mine, Calistoga Hot Springs, Napa County, California, USA
22.9km (14.2 miles) ⓘRosenhahnite occurrence, Russian River, Cloverdale area, Mendocino County, California, USA
25.4km (15.8 miles) ⓘSulphur Bank Mine (Sulfur Bank Mine; Sulphur Bank deposits), Clear Lake Oaks, Sulphur Creek Mining District (Sulfur Creek Mining District; Wilbur Springs Mining District), Lake County, California, USA
25.6km (15.9 miles) ⓘBaker Mine, Lower Lake, Sulphur Creek Mining District (Sulfur Creek Mining District; Wilbur Springs Mining District), Lake County, California, USA
27.0km (16.8 miles) ⓘCorona Mines (Vallejo Mines), Twin Peaks, Calistoga, Napa County, California, USA
References
 
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