Vote for your favorite mineral in #MinCup26! - Arsenuranylite vs. Talc
It's a pair of soft and lovely minerals as Stichtite and Talc compete for your votes.
Log InRegister
Quick Links : The Mindat ManualThe Rock H. Currier Digital LibraryMindat Newsletter [Free Download]
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsThe Rock H. Currier Digital LibraryGeologic TimeExplore Fossils
Minerals by PropertiesMinerals by ChemistryMineral Visual ExplorerAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsClubs & OrganizationsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral QuizTime Machine
Photo SearchPhoto GalleriesSearch by ColorPhoto Colour ExplorerNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

Opal from
Pinole prospect (Pinole Dohrman; Pawsey; Dohrman Pawsey), Bayview-Montalvin, Contra Costa County, California, USA


Locality type:Prospect
Classification
Species:Opal
Formula:SiO2 · nH2O
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Opal data
Locality Data:Click here to view Pinole prospect (Pinole Dohrman; Pawsey; Dohrman Pawsey), Bayview-Montalvin, Contra Costa County, California, USA
Data Identifiers
Mindat Occurrence Record ID:1005653
Long-form Identifier:1:3:1005653:0
GUID (UUID V4):0
Nearest other occurrences of Opal
37.0km (23.0 miles) ⓘFelder Mine, El Verano, Sonoma Mountains, Sonoma County, California, USA
37.7km (23.4 miles) ⓘBasalt Rock Company Mine, Vichy Springs, Napa County, California, USA
39.3km (24.4 miles) ⓘMount Pisgah Vineyard, Fetters Hot Springs, Sonoma County, California, USA
44.3km (27.5 miles) ⓘRichter deposit, Glen Ellen, Sonoma Mountains, Sonoma County, California, USA
46.9km (29.1 miles) ⓘWeise Clay pit, Weise Ranch, Glen Ellen, Sonoma County, California, USA
49.3km (30.7 miles) ⓘDiatomite occurrence (1), Oakville, Oakville Mining District, Napa County, California, USA
65.3km (40.6 miles) ⓘKellett Mine, Calistoga, Napa County, California, USA
71.1km (44.2 miles) ⓘGoodman Brothers deposit, Mark West Springs, West Mayacmas Mining District, Sonoma County, California, USA
74.9km (46.6 miles) ⓘCavagnaro prospect, Calistoga Hot Springs, Napa County, California, USA
76.9km (47.8 miles) ⓘCorona Mines (Vallejo Mines), Twin Peaks, Calistoga, Napa County, California, USA
References
Davis, Fenelon Francis & J.W. Vernon (1951), Mines and mineral resources of Contra Costa County, California: California Journal of Mines and Geology (Report 47): 47(4): 574, 610
Davis, Fenelon Francis and H.B. Goldman (1958) Mines and mineral resources of Contra Costa County. California Journal of Mines and Geology: 54(4): 521, 571, Pl. 5.
 
and/or  
Mindat.org® is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Mindat® and mindat.org® are registered trademarks of the Hudson Institute of Mineralogy.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2026, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph and Ida Chau.
Content on this site may not be used to train, fine-tune, or otherwise develop artificial intelligence or machine learning models without prior written permission - see our Terms & Conditions.
To cite: Ralph, J., Von Bargen, D., Martynov, P., Zhang, J., Que, X., Prabhu, A., Morrison, S. M., Li, W., Chen, W., & Ma, X. (2025). Mindat.org: The open access mineralogy database to accelerate data-intensive geoscience research. American Mineralogist, 110(6), 833–844. doi:10.2138/am-2024-9486.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: September 8, 2026 01:59:57
Go to top of page